After their Outlook.com accounts were moved to the new servers, a few people had problems accessing their email using ActiveSync:
Well, they moved my mailbox today, which is good. However, they broke the sync to my Windows phone. My phone displays a message saying:"Something went wrong
We can't sync right now. But you may be able
to find more information about this error code
Error code: 0x86000c1f"I did a factory reset on my phone and upon initial setup, signed back in with my Microsoft account. It configured everything on its own again (correctly), but mail sync is still failing with the same error. Maybe they don't care because there are only about 14 people with Windows phones???
No, it's not because no one uses Windows Phones. :) The Windows 10 Mail app is also affected.
My old Hotmail account was finally migrated to the 365 system, however it has now left a few glitches I can't rectify. The native Windows 10 mail/calendar app wont recognize that my Hotmail (which is also my primary Microsoft account) has migrated over. I initially tried to log in as an outside user, delete the primary account then re log in and have it re-add itself (if all that makes sense), but it keeps giving me a sync error Error Code: 0x86000c1f. Likewise in the one calendar app, when I try to add my Hotmail as an exchange account, it cant connect and asks for details like: email address, Server, Authentication (Basic or NTLM?), Domain, User Name & Password.
It's not a common error (and there is very little information about it online) because it is triggered by a large number of folders in the mailbox, many more folders than most people have.
The solution: reduce the number of folders in your mailbox, either by merging or deleting folders or moving them to a PST file in Outlook.
You can check the number of folders you are syncing in Outlook on the Web, go to Options, General, Mobile Devices and double click on the device. Note: users with this error will see 0 folders syncing.
If you are curious to know how many folders you have in your mailbox, you can use the macro at Print a list of your Outlook folders to create a list of folders in Outlook, then paste the list Excel to get a quick line count. While it will include all folders, even though not all are supported on (or will sync to) mobile devices, it will give you an idea of how many folders you have in Outlook.