Probably a password security setting on one or other PC.
It would help to know which version(s) of Windows yu are using, whether the drives are NTFS or FAT32, what security policies you have enabled, and whether you have any firewalls installed.
Samsung Galaxy S9 review
Wacom Cintiq Pro 24 and 32 review – hands-on
When is the next Apple event?
Qu’est-ce qu’Amazon Prime ?