This seems to be a common problem in PowerShell and Visual Studio, yet cases and solutions seem to vary a lot. Though seeing several similar questions, I didn\'t find a work
The following worked for me (from Stack Overflow question Add-Type load assembly from network UNC share error 0x80131515).
In files:
C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe.config C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe.config