Internal error: Failed to get path of 64 bit common files directory

I had the same exact question and did not have any other strings in the registry other than the one first string that points to the x86 Common Files directory. It was after seeing this section in the registry key located at  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion that the answer to solving this error message just instantly became so clear. 

If you go to the registry key located at HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion

For 64 bit systems which is what my setup is, there should be 2 items in that list pointing to the 64bit & 32bit versions of the Common Files directories. In my case, it was just as clear as the message itself that kept saying that it couldn't find the path to the 64bit Common Files directory. The only entry I had was  a string named CommonFilesDir (x86)  with the Data field value of C:\Program Files (x86)\Common Files

Simple solution to this weird problem is to create a new String Value by going to the Edit menu to New --> String Value

Name it CommonFilesDir

Then press Enter so it creates the new string value and double click on it so you can type in C:\Program Files\Common Files

Then press OK.

Problem solved!

Continue on doing whatever you were trying to do that kept bringing up this error message to confirm everything is normal again and that message doesn't pop up anymore.

What an amazing response! Your inquires left zero margin for the problem to remain unsolved. The issue was I had no line of binary for Program files\Common files. Your screen shot allowed me to see what was right under my nose the entire time. Thank you so very much for solving a 2 month headache!

I wish it were, I can find no information other then to change the registry path. Until then I cannot install a few important applications Any suggestions would be much appreicated

It is not something like a permissions or privilege  problem upsetting your install or any running of a program  is it?  Have you tried right-clicking on the shortcut to the program, or the .exe, or Setup.exe and selecting the "Run As Administrator" option?