Error: "This webpage cannot be displayed" when opening Help File
This is a security setting in Windows. Microsoft considers CHM files unsafe. If F is a network drive, that’s probably the issue.
WORKAROUND 1:
Rightclick on CHM file for Properties and check if there’s an Unblock button. Press it and then OK or Apply to eliminate the issue.
WORKAROUND 2:
Copy the chm file locally. Also try running the following: regsvr32 itss
