Install PL-2303 USB to Serial Adapter

I have an Acer TravelMate 2303LCi running Windows XP Home, and I think something is corrupt. I am trying to install a CablesToGo USB to Serial Adapter, model #26886 and get the same error message with the drivers either off of the internet or the CD. I have tried in normal mode and safe mode. The error is as follows when I click on the install icon the InstallShield Wizard opens and I click next, the the following windows error:
"InstallDriver.exe has encountered a problem and needs to close. We are sorry for the inconvenience." I choose not to send an error report. I have tried talking to the support staff at CablesToGo, but they are at a loss. I previously had a Dynex DX-UBDB9 adapter installed that went bad. I did however uninstall it's drivers before trying to install the new adapter.
Anyone have any suggestions.