Problems with IDE (1.6.4) installation

Background to this.
I run Win 7 Pro 64-bit. Thanks to some malware, Win 7 had to be repaired/healed. This was 5th jun2015.
As part of getting things up and running again, I thought it might be a good idea to update to 1.6.4. I had already done this successfully on a Macbook.
The installation completed after the unistallation of the previous version.
Other posters have had the same problem Cannot Load Keywords.txt re-install processing - Installation & Troubleshooting - Arduino Forum
On launching Arduino from the desktop icon, I got the error message as in the previous post referred to.
I have attached three images which show the path and contents of the new installation plus the error message.
The Arduino folder has sub-folders with the correct installation date of 13jun2015, but the Arduino Application date is the date of the repair.
Should I delete the entire Arduino folder from the Programs(X86) location and start again?
Any help appreciated
Thanks

PS I hope the attached images work as I couldn't find an easy way to insert - wary now of going near unknown image sharing sites

Arduino IDE installation 13jun2015 (1).PNG

Arduino IDE installation 13jun2015 (2).PNG

Arduino IDE installation 13jun2015 (3).PNG

A bunch of people have had IDE 1.6.x problems, including IDE crashes and bizarre compile errors, when they have an old 1.5.x installation. Those problems seem to be caused by out-of-date executables that the new IDE saves outside the IDE installation directory. In such cases it appears that the fix is to delete or rename the old "Arduino15" directory and re-install 1.6.x.

On Mac OS X:
/Users/username/Library/Arduino15

On Windows:
C:\Users\username\AppData\Roaming\Arduino15

Thanks John,
I did try your suggestion, but no joy
I suspect that this is a Windows problem.
Reinstalls don't work (1.6.4 comes up with the keywords.txt error and asks for Arduino reinstall, installing 1.0.5 comes up with keywords.txt error, now reinstall Processing)
I also get a message that 1.6.4 is already installed, but there is no sign of it in x86 programs.
I'm beginning to think that the game's up on this PC.
Unfortunately, my main coding PC also needs an update to 1.6.4 and has Arduino15 in roaming, so if that plays up, I'm stuffed.

After double clicking program shows up on screen , then is goes to starting sit for awhile and then goes out? Nothing with arduino shows up just the desktop.

Hello
I tried going back to an earlier version (1.0.5)
This is successfully located in the C:>x86>Aruino folder with all the examples, libraries etc.
Starting the application from shortcut or Windows Explorer gives the same result.
The Arduino "splash" comes up, followed by "problems loading keywords"; "could not load keywords.txt"; "please re-install Processing"
Withe the attempted 1.6.4 installation, the message is the same, bar "Processing" is now "Arduino"
This is the situation as it stands
1.6.4 has successfully installed on a Macbook and 1.6.5 is on a Linux (Ubuntu 12) laptop.
I'm starting to look around for a Linux solution which steers clear of Windows altogether, but I would still like to find out what is going on here
Thanks