This message indicates that the original installation files (the ".msi") are located on a network path that is either of the following:
-The user does not have access to the network path (not on the same domain) from where SolidWorks was originally installed. To verify this, try to open the directory shown in the "source" field in Windows Explorer.
-The directory/files have been deleted from the location shown in the "source" field.
If the files have been moved or deleted, the user will have to uninstall and reinstall from the new directory or a local image (DVD).