An error while importing .reg files in the registry:
The solution was to save the as US-ASCII in VS.
Deleting files older than X days:
forfiles /p [DirectoryPath] /s /m *.* /d -X /c "cmd /c del @file : date >= X days"
If VSTS test passes when run as "Debug" but fails mysteriously when just "Run" and test accessors are used, it is time to refresh test accessors. The best by deleting them and regenerating.