Probably. I am running 10.5 on windows 7. After installing 10.5 on Win 7 I initially got a "Can't find license file" error whenever I tried to start OrCAD (and OrCAD would not start). I was able to get past this by adding an environment variable to the system:
Variable Name: LM_LICENSE_FILE
Variable Value: C:\OrCAD\OrCAD_10.5i\tools\license.dat
If you have OrCAD installed in a different location, the path for the variable value needs to be changed accordingly.
I realize this thread went cold 2 years ago, I just wanted to record my findings in case anyone else had the same issue I had.
Yes, I could just upgrade to 16.3, but 10.5 is so much easier to use.