@DavidR,
Yes, he would need need turn off Avast Self-Defence. Thanks for pointing that out!
@william1657
If you have any version of Avast Antivirus installed, to turn off Self-Defence, please open the Avast application > click "Menu" in the top right corner > click "Settings" > make sure "General" is selected on the left hand side > click "Troubleshooting" in the central column > un-check "Enable Self-Defence" > click "Yes" on the warning popup. Once you are finished with the Bookmark files, please re-enable Self-Defence by checking the box again. Please see the attached screenshot for clarity if needed.