Your Support File Search Path (in the CAD Options dialog box under the Files tab) is likely set to a UNC path when it should be set to a letter drive.
You may need to ask your IT administrator for help with these steps.
1. Make sure Land F/X is mapped to a letter drive.
2. Correct the Support File Search Path so it points to the letter drive that's mapped for your Land F/X installation, rather than a UNC path.