Lyle
I can't really tell what your problem is as the syntax you have posted may not be correct it should be C:\Program Files (x86) (Note the space and the backslash), so if windows is recording the error as posted there may be something wrong with the paths to the railworks folder.
Firstly I would run sfc /scannow as here:
http://support.microsoft.com/kb/929833 this will fix any corruption in the system files.
What would be useful would be your pc specs, eg., cpu, RAM, mobo, graphics card, OS 32/64-bit with Service Packs and the actual path to your RailWorksProc2.exe file?
For example mine is: C:\RAILWAY Virtual\STEAM\steamapps\common\railworks\RailWorksProc2.exe.
Try the "fix" above and then we can go from there!
Good luck
PeterH