I've been running Windows 10 x64 Pro (Threshold 2 compilation). I used to run it independently from the domain for a couple of weeks and it was fast as a hurricane

However my company finally decided to put us all into a domain. I have no technical details, but my best guess is they are using Office 365 services to do so, as we certainly have no own network infrastructure of that kind.

My problem is that after joining the domain my boot time tripled! I have checked the group policy to see if there are any strange entries, but found only three items - network folders mapping, printers mapping and "My Documents" mapping into OneDrive for Business. I've run the Process Monitor but log examination revealed no time gaps or significant delays.

I've read at this and other forums that typically such delay is caused by the domain controller situated outside the local network, but I'm not sure of that. My problem occurs both when in local network and outside it (no network access).

Can anyone advise me how to investigate this issue? What can cause such a huge delay?