Hi nickp417,
I am not with Laminar Research; just a flight simmer.
The Steam version is not he same as the version purchased directly from Laminar Research. I am not aware of the installation process for the steam version as I don't have it and don't support its progress.
If the installation instructions are the same as the version from LR then you have installed the software incorrectly according to the manual and other comments by Laminar Research staff in this forum. It should be installed on the desktop or onto a dedicated drive to prevent any corruption within any of the windows files as you have done.
On the chance your problem is another issue, attach the Log.txt file to this question so that others with a greater knowledge base can advise on a possible resolution to your predicament. The log.txt file version to be attached is generated as soon as the software crashes or when you shut down.
In the meantime I would review the installation instructions and if there is an option to select your own location then I would do so eg desktop. But, in doing so, totally delete your current version first.
There is another possible quick solution but you are running steam.
Glenn