Well, your test was a success. It showed that the version of the driver you used doesn't install on Windows 7 beta. If you want to know why, I'm afraid you'll have to ask Microsoft and Nvidia. But I doubt if they will give you a satisfying answer.
Beta's may contain errors, and apparently this error was solved in the final release. Maybe - if you pay for it - Microsoft still has their incidents database to find the answer.
Yes, I know this is a beta, but I like testing systems, and other people never seemed to have to issues with this system. I posted this on BetaArchive but after multiple weeks, still have got no reply. Please do not question me and ask why and all of that, because you know why, I like to test. All I need is some assistance.
Here is my issue:
On testing PC upstairs, I installed Windows 7 Beta, where I test operating systems. I installed my network driver, I did slmgr -rearm to make it a trial, I changed the BIOS date and time to Jan 9 2009, but I cannot seem to be able to install my NVIDIA graphics driver. I have a NVIDIA GeForce GT 520 graphics card, and have been able to install this driver on all other versions of Windows that I have tested (including Vista, 7 (Final), 8, 8.1, and even 10), but it won't install on here. It says it is compatible and brings up the terms, but then once it starts installing, it stops, and says NVIDIA Installer Failed, and my graphics driver is not installed. In Device Manager, it is just labeled as Standard VGA Graphics, and when I update it with the files in the DisplayDriver folder, it restarts, and has done nothing. Please help.
TROUBLESHOOTING THAT I'VE DONE:
1. Updated the driver with the files in the DisplayDriver folder (DOESN'T WORK)
2. Tried to install it doing a clean install (DOESN'T WORK)
3. Tried installing it with only the graphics driver selected (DOESN'T WORK)
4. Putting the time back to normal then trying installing (DOESN'T WORK)
5. Installed DriverMax, DriverBooster (DOESN'T WORK)
6. Installed Driver Talent (just said it Stopped working)
NOTE: I don't mind if the solution is advanced, because this is my test PC and I do not have personal files on it.

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