Lately, I have seen a few posts on this subject.
I have used the following 2 methods, flawlessly since version 2.0.
My preference is method 1, which has never failed me, and is also in
Netscape's readme files.

1. Simply download the newer version and install over existing.
    Netscape replaces the older with the newer and all
    bookmarks/cache/mail/news remain intact.

2. Uninstall current version.
    The \netscape\user directories are NOT deleted.
    Install newer version. Voila, all bookmarks, etc. are all there.

If neither method works, then things have gone haywire.
In this case, uninstall current version, and backup the profile.
Clean out the registry of unwanted Netscape entries, delete any
lingering shortcuts(Netscape), delete Netscape directories, and start
fresh. Manually create a profile with the same name, and start Netscape.
Close Netscape. THEN, replace the new profile with the old.
This method has also worked for me on several occasions.

If none of these methods work, then the problem is likely not Netscape.

Regards,
Dharam

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