ZoneAlarm with MSN Mail Problem

This is somewhat FYI; I looked for anything similar without finding any posts, sooo, with some trepidation, here goes:
I've been having repeated problems accessing individual emails within MSN Mail (part of MSN9 Dialup) while using the free ZoneAlarm firewall on a Gateway GT4016 Windows XP Media Center. However, I have had no probs with MSN Mail (somewhat earlier version of MSN9) and ZoneAlarm latest with all updates on another computer (eMachine T4510 with Win XP Home). Specifically, what happened was that I'd be able to open new and old mail for a while, then would be unable to open new mail and would get a notice saying can't open this file, check my internet connection. At that point new letters would be listed with zero kb. Attempting to resolve probs on the Gateway, I repeatedly downloaded and reinstalled MSN9 despite being on dialup, finally getting a new CD from MSN. I also repeatedly downloaded and reinstalled ZA _ in case somehow there were a glitch incorporated during downloads. Also got an MSN email specialist's help via online chat at the MSN support desk. Ultimately, she and I determined that the problem didn't exist when ZA was off. Rebooting didn't help, enabling all MSN lists fully in ZoneAlarm didn't help. Problem would recur after uninstall/reinstall. Because of other probs, I reinstalled the OS from a Gateway recovery disk, re-established everything from scratch etc, and mail problem recurred. I've "solved" it by getting rid of the ZoneAlarm firewall on the Gateway and using Comodo. Otherwise, never did figure out what was awry.

Additional comment: Sure wish one could save on a CD all the updates to various programs such as Norton Systemworks, the various anti-spyware programs, etc., _rather than that they simply be auto-installed _ so those of us on dialup could do reinstalls as needed without literally hours of downloads. Anticipating question: No hispeed available at my house except via cable costing twice my MSN dialup _ or via satellite, I guess.