When processing Guest OS data through vSphere API, Veeam needs to deploy a runtime component in a temporary location. C:\Windows\Temp\ folder had been used for these purposes previously. However, starting from 10.2.0 VMware tools’ version, the Temp folder location has been changed to C:\Users\username\Temp\.
When User Profile Disks feature is used, Windows has no User’s profile temp folder unless a User is logged in (once a User is logged out, Temp folder is deleted). Hence, Veeam has no temp folder to place its components in.