Error 2355 is a MSI installer error and it means "corrupt cabinet," presumable meaning that one of the cabinets containing the actual files is corrupt. Apparently they have a bad installer volume. I would try sending them a new copy. I have also seen this result from a bad CDROM read. If they are installing from a CD, have them copy the install files to the hard drive and try installing it from there.
Best Regards,
Chris Matthews
National Instruments