I'm running into this too specifically with the Firewall.
101 devices but 5 of them aren't happy with 2016345612(Syncml(500): The recipient encountered an unexpected condition which prevented it from fulfilling the request)
Hybrid Joined with Auto Enrolment.
Confirmed the device name is under 15 characters.
Confirmed the firewall is on
Tried resetting the firewall to defaults.
Triggered syncs from Intune and from the client-side (Accounts->Work or School->Info->Sync)
Used the Company Portal 'Check Compliance'
Triggered syncs via
Trigger a compliance check via local process on PC (use remote shell or execute locally)
Start-Process -FilePath "C:\Program Files (x86)\Microsoft Intune Management Extension\Microsoft.Management.Services.IntuneWindowsAgent.exe" -ArgumentList "intunemanagementextension://synccompliance"
Trigger a sync via local scheduled task on PC (use remote shell or execute locally)
Get-ScheduledTask -TaskName “Schedule #3 created by enrollment client” | Start-ScheduledTask
Nothing is helping - to the extent I had to simply exclude them from the policy which is ridiculous... does anyone have any other bright ideas?