Microsoft 365 and Office | Other
Miscellaneous topics that do not fit into specific categories.
Hello,
I think you left out the most important detail -
What app is this, that you are trying to log into?
I can log in but although the system greets me, it asks me to log in again to access all areas
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Graeme Freestone King
0
Reputation points
I am having difficulty with valid sign in requests on my account ...
- There is a MS Account sign-in required to use a specific App on my Android device.
I can log in with my MS User name and password but the system then requets my keyboard PIN.
If I supply that, the system then returns this error:
Request Id: <removed PII>
Correlation <removed pii>
Timestamp: 2026-02-16T03:43:50Z
Message: AADSTS900561: The endpoint only accepts POST requests. Received a GET request.
On screen, the MS system tells me I am logged in but I cannot progress beyond this screen.
- On this PC, to move away from this page:
https://support.microsoft.com/en-gb/contactus
To try to gain help, I am again asked to log in, despite the screen greeting me by name and confirming that I am logged in:
When I input the same email address I have already used to log in, I am told it is not a valid email address and I can progress no further.
I assume that this may be an issue with the account type that I have but AFAIK, I have never had the option of a Business or Education account.
Would the fact that I am using a Home account, also be the reason for the problem encountered in (1)? If so, as that App is necessary for my work, how do I change to a Business or Education account?
Microsoft 365 and Office | Other
1 answer
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EmilyS726 211K Reputation points Independent Advisor2026-02-16T13:54:11.9166667+00:00 -
Graeme Freestone King 0 Reputation points
2026-02-16T14:52:54.26+00:00 The App is probably a little irrelevant, in that it's the inability to pass a certain point governed by Microsoft, rather than the App itself, which appears to be the issue.
The App is Campagnolo BlueService, a very specific App which does a highly proprietary job & which will be used by probably no more than 60 - 70 people worldwide.
Use requires multi-layered authentications.
On attempting to start the authentication process, the first step is to Sign in with Microsoft - Campagnolo make extensive use of external Microsoft IDs elsewhere in their IT systems. On tapping Sign in with Microsoft, an account selection prompt is arrived at.
If I select my MS account, I'm then prompted by the "Lets keep your account secure" screen.
Tap on "Next" and the system says "We couldn't sign you in" - whilst showing me as signed in on the same screen.
If I then tap on "Use another account" I get the normal MS sign in screen with an additional option, "Sign-in options".
As I only have one MS account, as far as I know, I tap on "Sign in options" and I'm taken to "Face, fingerprint or security key". If I opt for Passkey, I am invited to enter my keyboard PIN for the phone.
When I do that, the system appears to hang for 15-20 sec "Working" and then presents a message "We couldn't sign you in. Please try again" whilst showing me as signed in on the same screen.
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EmilyS726 211K Reputation points Independent Advisor
2026-02-16T15:02:55.63+00:00 That message is basically saying: the Microsoft sign-in service endpoint your app hit was expecting a form submission (HTTP POST), but something (the app, the in-app browser, or a redirect) instead tried to open it like a normal web page (HTTP GET). When that happens, Entra ID blocks it and returns AADSTS900561.
In plain terms: the sign-in flow got “misrouted” or “replayed” in a way the server will not accept. The app’s configured redirect URL is wrong or outdated (this is on the app vendor or your organization if it’s an enterprise app).
Also, since you are using this for work, have you tried using a work assigned account instead of your personal Microsoft account? If your work is using Microsoft business account, that can be all you need to sign in with.
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