The specified file could not be encrypted.
The solution turned out to be pretty simple:
1. Go to each file (or folder) giving you issues
2. Right click and select Properties
3. Hit the Advanced button
4. Uncheck “Encrypt contents to secure data”
5. Click OK, then OK on the other dialog (or APPLY)
6. Open (or preview) any file in the folder giving you issues
So why does this happen?
If Windows is storing your files in encrypted form, when the publish process attempts to copy the file, it tries to encrypt the file again and you get this error.
After clearing the encryption from the files, I was still experiencing the issue. It then occurred to me that the files might not get “decrypted” until I open them again which seems to be the case.