What we'll try is this:-

First uninstall Netscape 7.2 and any other versions of Netscape 6 or 7 that you have installed. (Netscape 8 is fine to leave alone).

Then open C:\Program Files\Netscape (or wherever you installed Netscape 7.2) and delete the entire folder. Also do this for any other versions of Netscape 6 or 7 that you uninstalled.

Now you need to find your Netscape profile. If you have a look at
this page at Ramona's website it'll tell you how to do just that.

Now make a backup copy of that profile, make a new folder in the C drive called Backup and copy the whole Netscape profile folder there. Now we've got a nice backup of your bookmarks, email etc.

Now delete the original profile folder since we have a backup. (the entire Application Data\Mozilla\ folder)

Now we've cleaned out all the gunk, we can try reinstalling Netscape 7.2. Grab a fresh copy from the
NSBA and do an install.
Hopefully this works for you.

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