Crash after Avast 5 upgrade?

I have been with Avast for ages, and have loved it. I saw my free registration period ending and decided that I would support this company by purchasing the Suite. I installed the license and rebooted my machine. It got to loading windows then a BSOD flashes on the screen and immediately reboots. This is a Vista Home Premium 32 bit version. I tried this also on a same operating system but on a laptop. It also failed to restart, however it successfully ran the automated repair. After it did finally boot, it came up unprotected. The auto-fix feature apparently corrected this, but with my desktop the auto-repair didn’t work and it has been running the prebuilt scans under the repair partition. There have been no errors so far with those. I have to wonder about this because it affected two computers in nearly identical fashions. I can’t imagine I did something wrong, since it’s really not difficult to install the license file. Any suggestions?

Uninstall avast. The next time, download avast IS/PRO installer and insert the appropriate license. Upgrading from Free seem to result to a BSOD. It is better if you download a trial of IS/PRO and insert the license.

Thanks!