Hello Bill,
If you have a corrupt DLL, the best thing to do is to remove it manually. Turn off the computer and uninstall the hardware, then uninstall all the software that you can using Add/Remove Programs. The National Instruments software will all be under the National Instruments entry in the Add/Remove Programs list. Then search your computer for the corrupt DLL to make sure it gets deleted. You can also delete, manually, any entries under Program Files that are associated with the corrupt file. Once this is clear, reboot and check to make sure the files are still gone, then reinstall the software. Also, check that the computer crashing did not break any of the hardware you had installed.
Hope this helps.
Regards,
Angela
Applications Engineer