basically, if an MSI is launched without full
permissions and the Everyone user does not have FULL permissions on the
window temp and users profile temp folder, the installation will fail
with error 2503 and/or error 2502. the REF video shows how I work around it (no audio), just get to an admin cmd prompt and launch the MSI and voila, otherwise change perms on the %temp% and c:\windows\temp folder to include everyone full perms.