If you’re running into the following error trying to get a device to sync with Intune:

The sync could not be initiated (0x80190190)

You probably have checked the Windows Event Log and also seen this error:

MDM Session: OMA-DM message failed to be sent. Result: (Bad request (400).).

I recently ran into this situation, and the cause was that I had opted into the Windows 10 default of signing in with a Microsoft Account. Under “Access Work or School” in Computer Settings, it showed both my work account and home account.

If you try to remove your home account, you might get an unhelpful error that “This PC isn’t joined to a domain”.

The solution for me was to:

• temporarily move to signing in with a local account
• Disconnect all registered work accounts
• Re-connect the work account (just disconnecting the Microsoft Account doesn’t resolve the problem)
• Move back to signing in with a Microsoft Account

After that was done, the error should go away and you should again have a healthy Intune managed machine.