ERROR: "Bad Request - Request Too Long" When Signing In To Microsoft 365 Using Work Profiles
When the following conditions are true: Using the latest version of Microsoft Edge browser. When the browser is signed in to any Microsoft 365 account. When browsing to any Microsoft 365 website. I receive the following browser error: Bad Request - Request Too Long HTTP Error 400. The size of the request headers is too long. When I sign in to any Work Profile, no matter the account/tenant, the moment I browse to any Microsoft 365 page i.e. any website that redirects via: https://login.microsoftonline.com/, I receive the error above e.g. https://office.com, https://admin.microsoft.com, https://portal.azure.com etc. If I sign-out from the Work Profile, everything works fine (i.e. I am presented with the usual Microsoft 365 sign-in dialogue for username and password, then 2FA code, then the expected page appears), if I then sign-in > browse > error ... sign-out, works fine, sign-in, error etc. ... consistently repeatable. Using 'Browse as Guest' or any 'Personal' or 'Work Profile' without signing in works fine. TROUBLESHOOTING ALREADY CARRIED OUT Deleted/recreated all profiles. Signed in / out multiple accounts on multiple tenants. Sync options > all, some, none. 'Automatic sign in on Microsoft Edge' enabled & disabled. 'Allow single sign-on for work or school sites using this profile' enabled & disabled. 'Automatic profile switching' all options on & all off. Deleted all cache/cookies, from all time in all profiles. Reset settings in all profiles. Completely uninstalled/reinstalled Microsoft Edge (i.e. Safe Mode > delete all files > all profile data> all temp files > all registry entries). Q1 What could cause this error, only when the Work Profile is signed-in? Q2 Aside from syncing settings, how would signing-in to the Work Profile effect OATH requests to https://login.microsoftonline.com/? Q3 Has anybody experienced this or something like this before? Q4 Are there any troubleshooting steps I haven't tried?Microsoft 365 apps say farewell to Internet Explorer 11 and Windows 10 sunsets Microsoft Edge Legacy
This blog tells that: The Microsoft Teams web app will no longer support IE 11 starting from November 30, 2020. The remaining Microsoft 365 apps and services will no longer support IE 11 starting from August 17, 2021. If you are a customer who is using/developing apps based on Internet Explorer or Microsoft Edge Legacy, want to know the support cycle of IE11 and Microsoft Edge Legacy or about the shipping of Microsoft Edge Chromium on Windows devices, I would recommend you to read the blog published by Microsoft365_MicrosoftEdge_Product for more details which are as follows: https://techcommunity.microsoft.com/t5/microsoft-365-blog/microsoft-365-apps-say-farewell-to-internet-explorer-11-and/ba-p/1591666?WT.mc_id=modinfra-0000-abartolo
