Exposing Dynamics 365 APIs via Custom Connectors in Power Platform

Ever tried connecting Power Automate to Dynamics 365, only to hit
a brick wall with the standard connector? You're in the right
place. Today, we're exposing the exact steps to break through
those limitations—no more workarounds or hair-pulling. Curious to
see how custom connectors can instantly solve your toughest
integration headaches?


What Happens When Standard Connectors Hit a Wall?


If you’ve ever built a flow and reached the finish line only to
realize the Dynamics 365 connector won’t fetch that one field,
you’re not alone. It’s strangely common. You might have all the
standard triggers and actions set up, but the moment you need
something beyond basic records—a custom table, a calculated
column, or more flexible filtering—it just doesn’t show up.
Suddenly, your flow is only half as useful as you hoped. And the
worst part? It’s not obvious at first glance which pieces are
missing. It feels like staring into the fridge at 6 p.m.—plenty
of stuff there, but nothing that adds up to an actual
meal.Picture a typical team trying to use Power Automate to
manage daily business processes in Dynamics 365. Maybe it’s about
moving customer leads from point A to point B or syncing support
tickets to an external dashboard. Everything should just connect.
But when the process calls for grabbing a value from a custom
entity—let’s say “Warranty Claims” or “VIP Account Status”—the
standard connector just shrugs. That data simply isn’t exposed.
So, someone prints out a report, walks across the hall, and
starts copying values by hand. It’s 2024, and we’re suddenly back
to the days of double-entry. If you’ve ever listened to coworkers
grumble about retyping the same number in two different systems,
you know the feeling. There’s just that undercurrent of “why
exactly are we doing this?”The workaround phase starts here.
People give up on automation and settle for a parade of Excel
downloads, copy-paste sessions, or, if they're more daring,
spinning up some half-documented flow that scrapes data from
emails or exports. Meanwhile, every new request gets punted back
to IT with the same answer: “Sorry, the connector doesn’t support
that.” The reality is, manual workarounds aren’t just slow.
They’re open invitations for mistakes. Typing errors, missed
updates, and mismatched data have a way of stacking up. And those
little discrepancies—or big ones, depending on your luck—turn
into lost revenue, bad reporting, or frustrated clients down the
line.If you zoom out to watch a full week in one of those
organizations, you’ll see some classic symptoms. Someone spends
part of every Friday yelling at their screen because a scheduled
flow ran but didn’t actually update the critical custom field.
Monday rolls around and someone else spots the error, but only
after a customer points it out. Management holds another meeting
to talk about “digital transformation.” Meanwhile, teams are
resending invoices and apologizing for delays that automation was
supposed to fix in the first place. Microsoft’s forums and Power
Users groups are full of threads where admins plead for help
getting data out of custom entities or applying more advanced
filters—usually met with a mixture of sympathy and “you’ll
probably need a custom connector for that.”Advanced filtering is
another big source of frustration. Let’s say you want to pull
only records changed in the last 48 hours, or filter based on a
calculated status. The default connector might handle simple
queries, but the moment you want to slice data a bit finer, you
hit restrictions. This isn’t just a technical nuisance—these
missed granular details might mean your sales dashboard isn’t up
to date, or your compliance workflow skips over key cases. For
some teams, the inability to fetch a small detail from Dynamics
means the automation puzzle just never gets finished. There’s
always a piece missing.You can see the pattern repeat in every
discussion about Power Platform’s promise versus the actual
day-to-day. The marketing says automate everything, connect
anything, let your teams focus on what matters. The lived reality
for admins and business users is a bit messier. Instead of
eliminating busywork, sometimes Power Automate just reshuffles
it, moving the manual effort from the field team to a “data
specialist” toggling between screens. When a connector doesn’t
surface the one field you need or fails to trigger on an event
unique to your business, you’re left asking: Is this actually
making things better, or just making the same work look more
modern?Plenty of interviews and community Q&As showcase that
irritation. Power Platform forums are filled with folks wrestling
with the same handful of limitations, swapping tales of feature
requests, add-on solutions, and of course, workarounds that
involve more steps rather than fewer. It’s not a niche problem.
In fact, mentioning “custom connectors” in those spaces is almost
like using a secret password that signals you’ve moved beyond the
basics and are ready to actually solve the problem—without
waiting for Microsoft to add support three releases from now.If
you’ve ever felt that sense of frustration—seeing a world of
automation just out of reach, thanks to a missing connector
feature—you’re not imagining things. The spot where the standard
connector gives up is usually where the business needs things to
“just work.” And if you don’t stop to notice those gaps, you can
end up automating a workflow that still needs just as much manual
cleanup.So, the very first step is to actually pinpoint which
Dynamics 365 endpoints or features aren’t supported—because once
you’re clear on exactly what you’re missing, you can finally
decide if building your own connector is the answer. For most
people, though, the question that follows is: even if you know
the connector can’t help, how are you supposed to find that
hidden Dynamics 365 API endpoint you actually need?And this is
usually where things start to get a lot more interesting.


Finding the Right Dynamics 365 APIs—Without Losing Your Mind


If you’ve ever tried to pull a single field out of Dynamics 365
using Power Platform, you know the documentation rabbit hole that
follows. You realize it’s not about just finding an API—it’s
figuring out which of the hundreds of options actually gets you
what you want. Dynamics 365 exposes a massive set of APIs, and
every time Microsoft changes a feature or renames something,
another endpoint surfaces somewhere in the mix. It’s less like
opening a neatly labeled toolbox, and more like sorting a drawer
where every tool half-matches the label.So, let’s say you’re
staring at your flow, blocked by the standard connector. You’re
ready to hunt that missing data field, but now the real detective
work begins. The official docs are thick enough to double as a
doorstop, and even with a map it’s not always clear which route
to take. Sometimes you think you’ve pinned down the right API,
only to find that it’s deprecated or missing the action you need.
Other times, you stumble onto endpoints marked as “preview” with
a quiet warning that they may change any time. Then there’s the
maze of naming—one entity is listed as “accounts” in one corner,
“customer” in another, and the table name might use an older term
from Dynamics CRM days.If you’ve been at this for a while, you
know how quickly an afternoon can disappear just trying to match
real business needs with the right endpoints. The kicker is, some
endpoints seem designed for legacy clients, some use OData v4,
some are tailored to newer Web API conventions, and others only
exist for backward compatibility. Let’s not even start on SOAP.
Just unlocking the specifics about which endpoint lines up with
your custom data model can feel like reading a crossword puzzle
where half the clues are swapped out every version.Here's where
things can really go sideways. Say your business has a custom
entity—maybe “Warranty Claims,” “Special Pricing Configs,” or
some edge-case table from an ISV solution. You search the
documentation, but no clear API reference jumps out. Instead, you
flip through forum posts and realize others have hit the same
wall. One admin spends a night digging through the metadata
browser, another runs Fiddler to watch what happens when the
Dynamics UI loads that data, and a third just gives up and calls
for outside help. Even getting the entity name spelled correctly
is an adventure—schemas, logical names, display names, and case
sensitivity can all trip you up.When the endpoint finally
surfaces, it might not quite fit what you imagined. Maybe it
returns all records, but filtering is awkward. Or it wants a
totally different authentication flow. Worse, sometimes you get
access to more data than you intended, raising the risk of
leaking sensitive records if you aren’t careful with permissions.
Suddenly, what should have been a simple data retrieval becomes a
game of “what did I just expose, and who can get to it?” Everyone
wants that Goldilocks zone: not too much data, not too little,
and only what your business role actually needs.A lot of teams
rely on Microsoft’s API Explorer, and it’s actually a strong
starting point—when it works. It lets you probe the available
endpoints, poke around with live queries, and see how Dynamics
interprets your requests. But if you want a deeper dive, tools
like Postman or Fiddler give you a window into what’s really
happening under the hood. By capturing traffic between your
browser and the Dynamics server, you can reverse-engineer the
exact requests the UI is making—sometimes exposing unofficial
endpoints that don’t show up anywhere in the documentation. Fair
warning: that shortcut comes with its own risks, since
undocumented APIs can disappear overnight.There’s a learning
curve around permissions, too. Not every API you discover will
honor your security model. You might get a 401 error, or worse,
find out your test user can see data they shouldn’t because a
misconfigured privilege in Dynamics was copied forward into the
custom connector. Preview APIs can also be their own brand of
headache. They might look stable, but a feature in preview often
means the endpoint, property names, or even the way it
authenticates can change, breaking flows without warning.Naming
inconsistencies are one of those “I thought it was just me”
problems, except everyone has a story about calling a field
“PriceTier” only to find the logical name somewhere is
“new_pricetierlevelid.” When you look at the entity metadata,
Dynamics helpfully lists out properties that look right until you
try to filter by them. There’s a certain art to cross-referencing
logical names, schema names, and the display labels that show up
in the UI—and a lot of trial and error before you know you’ve
really landed on the right endpoint.Once you actually find that
target API and can pull a test response in Postman, there’s a
real sense of relief. No more guesswork about what’s available or
supported—you’ve got proof in hand. The trick is, from here,
you’re one step away from surfacing that data in Power Platform,
but with every victory comes a new risk. Just because the
endpoint exists doesn’t mean it’s ready for primetime in a
production flow. You have to ask: does this API require
specialized authentication? Could it introduce data governance
headaches if reused across teams? That’s the part often
overlooked—one wrong configuration and you’ve bypassed all your
organization’s security guardrails.So, the real takeaway isn’t
just about tracking down an endpoint—it’s making sure you
understand what you’re exposing, who can access it, and whether
the permissions line up with your business needs. When you master
smart API discovery, suddenly those “impossible” automation
scenarios become solvable. No more playing 20 Questions just to
get your data. You’re ready for the next step: plugging these
hard-earned endpoints into Power Platform—but everything hinges
on getting authentication and governance right the first time, or
risk opening an entirely new set of problems.


Securing and Governing Your Custom Connectors


So you’ve finally surfaced that elusive Dynamics 365 API and
you’re itching to wire it into Power Platform. But before you get
lost in a wave of “look what I automated,” there’s a reality
check: exposing your API with a custom connector means you’re not
just opening doors for your flow—you’re potentially opening them
for everyone. If you think about it, a powerful new connector is
a lot like a skeleton key. In the right hands, it can save hours;
in the wrong hands, it’s a security exam waiting to happen. Most
people don’t notice the catch until it’s too late. Suddenly
you’ve got flows accessing data they shouldn’t, users running
reports on information never approved for their eyes, and a heap
of owners trying to figure out who’s responsible when something
goes sideways.It’s not just theoretical, either. There are
cautionary tales buried all over Tech Community threads—an
enthusiastic admin introduces a handy new connector, only to
realize a week later that a misconfigured permission lets interns
browse confidential sales deals, or someone copied a flow
verbatim across departments and now HR data is mixed into
ticketing requests. Sometimes the issue is too-simple
authentication. Teams say, “we’ll fix this in phase two,” then
get distracted. Suddenly, a single stagnant client secret, shared
across half the company, is all that’s separating your private
CRM from the curious intern on summer break.Choosing the right
authentication scheme makes a difference, and it’s not
one-size-fits-all. OAuth2 gets thrown around a lot for its
granular permissions, but setting it up through Azure Active
Directory involves extra steps—app registrations, callback URLs,
scopes, and user consent screens. If you stick with API key or
basic authentication, yes, configuration is easier, but that
convenience comes with strings attached. A hardcoded secret in
your connector makes life simple until it leaks in a Teams chat
or ends up buried in an open repo. Suddenly you’re not just
worried about the right people accessing data, but about removing
a secret from a dozen flows when someone leaves.Azure Active
Directory (Azure AD) App Registrations are where Microsoft gently
nudges everyone now. You register an app, define permissions, and
use it to handle authentication securely between your custom
connector and Dynamics 365. It’s a bit more work up front, but it
gives you leverage later—for both auditing and governance.
Microsoft calls this “least privilege,” meaning your connector
only gets the absolute minimum access needed to do its job, not a
blank check to read every table in the database. Service
principals—essentially non-human accounts—fit well for background
tasks, scheduled flows, or scenarios where you want automation to
keep churning when someone is out sick. User-delegated
permissions, on the other hand, are for those situations where
you want every action attributed to a real person. That becomes
crucial during audits—because five months from now, when someone
asks who updated all the credit limits last quarter, you’ll want
a log that points to an actual user rather than a generic “system
process.”Not every organization has the size to worry about
connector certification or formal governance, but it’s remarkable
how quickly things spiral even in small teams. Connector sprawl
is real. Without centralized management—assigning an actual owner
to each connector, setting permissions, carrying out periodic
reviews—you’ll find multiple versions of the same connector
floating around, each tweaked for a different scenario. Bigger
companies have started bringing custom connectors into their
software certification programs—think code reviews,
documentation, approval gates—just to slow down proliferation and
keep tabs on who has access to sensitive APIs.Role-based access
control (RBAC) within the Power Platform helps cut down risk. You
map connectors to security groups, limit who can install or run
them, and integrate with existing Azure AD roles. That approach
gives you a chance to police not only who can build a connector,
but who’s allowed to use it in production. For example, maybe
only managers in the finance group can launch a flow that pulls
salary data, while everyone else gets an error—even if they have
access to the connector itself. And while Power Platform’s
built-in monitoring and logging might seem overkill when you
start, it becomes indispensable the first time someone asks for a
trail of “who changed what, and when.”Now, here’s the curveball
hardly anyone talks about: versioning. Creating a connector is
one thing—managing its lifecycle is another. APIs evolve. Fields
get renamed, endpoints move, authentication methods upgrade as
security standards march forward. Without a plan for versioning
your custom connector, you’re left dreading the day when a
Dynamics 365 update quietly breaks every flow in the building.
Some teams address this by copying the connector, slapping a “v2”
on the name, and updating flows piecemeal. Others bake in
versioning from the start—using different environments for test
and production, documenting changes, and alerting teams before
upgrades go live. It might seem like bureaucracy, but it’s the
difference between a predictable outage and an afternoon of
urgent Teams calls.The real power of custom connectors only comes
out when you blend the flexibility of Dynamics 365 APIs with
airtight governance and careful authentication. You get the best
of both worlds: flows tailored perfectly to your business, and
the confidence that nobody’s sneaking data where they shouldn’t.
It’s easier to keep things neat if you tackle these issues up
front instead of chasing problems after rollout. But even the
most organized teams find that new layers of complexity creep in
as usage grows. One solution works with ten users, but how does
it hold up when a hundred people are running flows against the
same connector, or when Dynamics 365 adds new fields overnight?


From Clunky to Seamless: Real-World Payoffs and Performance
Lessons


Picture a typical month before a custom connector lands: sales
teams copy orders from a partner portal into Dynamics 365, line
by line, juggling browser tabs and pasting in discounts or
tracking numbers. Mistakes slip in—an extra zero here, a skipped
address there. Reporting always runs a day behind. Nobody’s
excited about reconciliation at month-end, and there’s a constant
low-level hum of “why can’t this just update itself?”
Fast-forward after a custom connector is deployed, and that
manual mess is gone. Orders come in through the portal, and
within minutes, new sales records show up inside Dynamics.
Discounts always flow through as intended. The folks who usually
fix spreadsheet errors now have time for something better. You
see it in feedback too—staff joke about having “nothing left to
double-check,” and the finance lead only needs one espresso as
opposed to three.Of course, the good times only last if you
design with more than a handful of orders in mind. When traffic
is steady and predictable, things hum along. The moment a
marketing campaign works a little too well and order volume
jumps, though, performance issues sneak in. Suddenly, that
connector’s being hit sixty times a minute instead of six, and
rate limits aren’t just a technicality—they’re a full stop.
Microsoft’s APIs tend to, very politely, shut the door when you
overload them. Instead of seamless automation, you start seeing
errors pile up in flow run histories. Transactions hang, retries
stack, and the outcome feels suspiciously like the old
double-entry days, just with an extra layer of complexity.Take
one organization that synced incoming web orders into Dynamics
via a custom connector. Everything ran fine at first. Then their
seasonal sale hit, and the Power Platform flows started tripping
over 429 “Too Many Requests” errors around noon each day. The
lesson? It’s not enough to build the connector; you need planning
around throughput. Error handling moves from a nice-to-have to
essential overnight. Successful teams set up auto-retries with
reasonable back-off times, so if Dynamics pushes back, records
aren’t lost—they just wait and try again. Testing shouldn’t just
mean a quiet Tuesday afternoon; it means throwing sample loads at
your connector to mimic the busiest week of the quarter.But
performance goes beyond pure volume. As Dynamics 365 evolves,
APIs shift. Names change, filters update, endpoints get new
security expectations. The teams that keep their connectors
humming aren’t relying on a set-it-and-forget-it mindset.
Versioning matters, and here you see differences between band-aid
solutions and future-proofing. Some build out a clear versioning
model—every major API change triggers a new connector version.
They communicate updates, give teams time to migrate their flows,
and archive the old versions after validation. It’s the
difference between a crisis call at midnight and a
Friday-afternoon notice to review changes next week. It can help
to use descriptive names—“SalesOrderSync_v1,”
“SalesOrderSync_v2”—and keep an internal changelog for what each
version fixes or updates.Monitoring is another area that’s easy
to overlook until something fails. Standard flow analytics inside
Power Platform get you as far as basic success/failure rates, but
the teams running mission-critical automation set up custom
logging and error notifications. This means tracking not just
failures, but unusually slow runs, repeated retries, or
suspicious spikes in API usage. Advanced teams use Azure Monitor
or Application Insights to catch early warning signs, but even a
simple Power Automate flow that emails the owner on repeated
failures puts you ahead of the game. When things go off-script,
you want alerts routed somewhere they’re seen—not buried in a
forgotten mailbox.Then there’s governance, which sounds more
bureaucratic than it is. The minute more than one team starts
deploying custom connectors, you need structure. Assign an
owner—someone technical enough to maintain it, but close enough
to the business to understand its role. Define lifecycle policies
so connectors don’t hang around unused and unmanaged. A quarterly
review can catch connectors that rely on deprecated endpoints,
use authentication methods you’d rather retire, or have open
access that wasn’t intentional. Without active ownership,
connector sprawl grows. That’s how you end up with five nearly
identical connectors floating around, each with slight
differences, none of them officially supported.The payoff for
doing this right isn’t subtle. Orders sync as soon as they’re
placed; teams trust that what they see in Dynamics 365 matches
reality. When new features are needed—maybe a new sales promotion
with unique discounts—you add capabilities to the existing
connector instead of piecing together another workaround. If the
API for orders changes next quarter, you’ve got the versioning
discipline to adapt without breaking a dozen flows
overnight.Building for performance means respecting rate limits
and architecting fail-safes. Governance means giving someone real
accountability so connectors aren’t forgotten or misused.
Monitoring means problems get addressed before they become fire
drills. When you get all this right, custom connectors do exactly
what the Power Platform marketing promises—they quietly automate
the background work, scale up as business grows, and keep
sensitive data where it belongs. Teams stop thinking about
“getting the data in,” and start asking what’s possible now that
the plumbing works the right way.


Conclusion


If you’ve worked with Power Platform for any length of time, you
know how often a “standard” solution is only half the answer.
Custom connectors close that gap. Suddenly those missing Dynamics
365 features move from wish list to working reality. You get
consistency, control, and, finally, automation that matches how
your business really operates. Building your own connector isn’t
just for developers with a weekend to spare—it’s for anyone tired
of compromises. Give it a try, and watch your automation toolkit
expand. If more stories like this are useful, hit subscribe and
let me know what integration challenge is driving you up the
wall.


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