I had a situation where users who should be logging on with roaming profiles loaded from a DFS share, were getting logged on with a local profile.
After browsing the logs, we could see that the profile wouldn’t get loaded because of a slow network link.
Which could be the case since users switch offices all the time.
The default policy is to check wether a slow link exists (500kb by default) and if so, windows will log you on with a local or cached profile.
To disable the slow link detection, you need to edit/create a gpo , Computer settings\Policies\Administrative Templates\System\Group Policy
Now you need to enable the policy and set it to “0” to disable detection,or define a speed you like.
Now when this is done, you also need to modify another policy under the user profile section (Computer settings\Policies\Administrative Templates\System\User Profiles)
You only need to enable the 2 marked in the screenshot, the other ones I enabled are not for this issue.