Hi,

I'm trying to install several apps (Firefox, Thunderbird, etc.) on an older
machine running Win98 First Edition. However, the Setups crash after
"Checking archive integrity" without further notice, i.e. no dialog boxes,
log files etc.
Some other post referred to problems with the Microsoft Installer. I have
tried to reinstall this; the result was something like "Service already
present" and installation aborted. I have also disabled all Startup entries
via MSCONFIG and rebooted, but the Setups still fail.
(Firefox and Thunderbird run fine when copied to that machine via XCOPY).

What is going on here and what needs to be done (without reinstallation of
Windows)?

Thanks,
Andreas