Thanks for your help
Please use Windows to search your PC for the file named "gtol.sym". Once you have found the file, follow the instructions on the error message you posted.
Once you find "gtol.sym", the error dialog doesn't state which location to set in File Locations.
Select "Symbol Library File" in the dropdown and see what your current setting is.
As Mr. Brady stated, this location must match where your file actually is.
Your file is probably in the same path as mine, except perhaps, for a different SW version or a different language.
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