[c#] Couldn't process file resx due to its being in the Internet or Restricted zone or having the mark of the web on the file

Complementing @lasse-v-karlsen answer. To unblock all files recursively, run from powershell as administrator inside the folder you want:

gci -recurse | Unblock-File

source link: How to Unblock Files Downloaded from Internet? - Winhelponline
https://www.winhelponline.com/blog/bulk-unblock-files-downloaded-internet/