I was getting error popups at login saying

CCAPP.EXE: "The ordinal 129 could not be located in the dynamic link
library MAPI32.dll"
and same for "ordinal 21"

CCAPP is part of Norton Internet Security.

Mozilla installs a MAPI32.DLL in Windows\System32. I replaced it (it
was version 1.5.20030.17168) with the old version from another Win XP
PC that did not have Mozilla (version 1.0.2536.0) and the problem has
gone away. Warning: this may break Mozilla email. Mozilla email still
works for me however.

I also sometimes got messages that CCAPP.EXE had crashed during logon,
and once got a message "Symantec User Session failed. If you were in
the middle of something your data may have been lost." After that email
did not work till I restarted Norton.

I tried reinstalling the Norton Internet Security but that did not
help.

Thanks to http://Techguy.com for pointing me to the solution.

Using Symantec Internet Security 2005, Mozilla 1.7.5 (for email),
Firefox 1.0.4, Windows XP SP 2. Also had earlier Mozillas 1.3, 1.5b.

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