I have a user who's links to folders on a network share stopped working. Last week they worked, this week they do not. The link is supposed to (and does on other machines) open the folder in windows explorer, displaying the folder contents.
The specific error message that comes up is: "The address of this site is not valid" or "Cannot open the specified file"
This file still works fine on other PCs. It is only a problem on this one machine that worked as of last week.
The network paths are all established on logon. (Though, the links in this case are not using a drive letter, but instead are using a UNC path.) Rebooting does not fix the problem.