Can anyone help me with a run-time error?

The error reads : run-time error ‘-2147221014(800401ea)’:
Cannot open the specificied file

What I want is to put the program on network for all to use to pull up pdf files
I can open the pdf file on computer no error
When someone else tries to open the hyperlink, this when the error show up.

This is part of the VBA code to open pdf file
ActiveSheet.HyperLinks.Add Anchor:=Selection, Address:= _
"F:\QUALITY\FINAL INSPECTION REPORT\" & a & b, TextToDisplay:= _
"F:\QUALITY\FINAL INSPECTION REPORT\" & a & b
Selection.HyperLinks(1).Follow NewWindow:=False, AddHistory:=True

Thanks