Here are some options for you.
1. The title to look for in Windows 98 Add/Remove Programs is "Netscape Communicator" which is the name given to Netscape versions 4.0+ (and maybe earlier). Is that item missing?
2. Why remove Communicator? Netscape 7.xx is independent of Netscape 4.5+. Both programs may even be run at the same time. It is a good idea to keep Communicator in case you do not like Netscape 7.xx, or you prefer the Mail in NS 4.5+.
3. My last suggestion is a little more drastic. Re-install Netscape 4.75 (it can be downloaded from the archives at SillyDog). Install it in the same directory as you had installed it before and try to pick the same options.
Now you should find Netscape Communicator listed in the Add/Remove list.
4. Wait for better advice.
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