I ran into an issue with some Windows 7 PCs at a client’s site. The PCs could not access network shares. Further investigation showed that PCs were online, and connected to the network. They all had internet access and could ping each other and the gateway.
However, when trying to access a share on these PCs, we received a “Handle is Invalid”, or “the network resource is not available”. Access the share via “\\computername” or “\\IPaddress” would not work.
The issue appears to be caused by KB4480970 – Monthly Cumulative Security Quality Update 2019-01. Various threads on Reddit indicated that there were issues.
Apart from a rollback and uninstalling the patch, a workaround for this issue appears to work. This involves adding the following registry entry.
- Browse to HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
- Add DWORD LocalAccountTokenFilterPolicy = 1
- Reboot the PC
Come on Microsoft! Test your patches more thoroughly!