I experienced a similar issue when not connected to my work network via VPN. Running the following from a command window worked for me:
net use H: /delete
This command actually deleted the H drive. If you actually use the mapped drive that is causing the issue, then this way could cause you other problems that would only be solved by remapping the drive (net use H:, followed by the mapped drive path). As a note, I did delete the HOME% variables (using “set HOME=” from the command line), but it did work until the command above was run.