Uninstalling Palm Desktop does not delete the user folders, so that's why the file is still there. Check the following paths under C:\program files\palm\<your user name>
QuickInstall\ExpCard
Install
CardInst
The file is probably sitting in one of those folders.
For the record, it's a bad idea to install large amounts of data via Quick Install. You're better off popping your SD card in a card reader, or using software like
Card Export, which lets your pc see the card in your Treo as an external drive.