If IE5 is install on a your computer, an OL98 install will crash.
IE5 won't run the unsigned binary files that OL98 uses to install.
You can workaround this problem by modifying the default security zone setting
for Local Intranet zone to allow Download unsigned ActiveX controls.
You can do this in batch, using Regedit /s <Drive:>\Folder\DUAC.REG where DUAC.REG contains:
NOTE: 00000000 is allow Download unsigned ActiveX controls
00000001 is prompt
00000003 is DO NOT allow Download unsigned ActiveX controls