Post upgrade to Mavericks, applications won't open on main user account but seem fine in another account.

Question

MBP Mid 2012.
Upgraded to Mavericks from Mountain Lion. The user account I was using when performing the upgrade now won't open any applications. In another user account on same computer, everything works fine.
When I click on an application the desktop picture goes blank before returning and nothing happens with the application. I can open folders but nothing else.
I've tried every fix I can find, but no success yet. I've reset the Pram, repaired disc permissions, re-installed Mavericks over the top, deleted all .plist  files, repaired disk with disk utility etc.
Any ideas and help would be appreciated.
Tod.

Answer 1

Back up all data before proceeding.
This procedure will unlock all your user files (not system files) and reset their ownership, permissions, and access controls to the default. If you've intentionally set special values for those attributes on any of your files, they will be reverted. In that case, either stop here, or be prepared to recreate the settings if necessary. Do so only after verifying that those settings didn't cause the problem. If none of this is meaningful to you, you don't need to worry about it, but you do need to follow the instructions below.
Start up in Recovery mode. When the OS X Utilities screen appears, select
          Utilities ▹ Terminal
from the menu bar. A Terminal window will open. In that window, type this:
res
Press the tab key. The partial command you typed will automatically be completed to this:
resetpassword
Press return. A Reset Password window will open. You’re not going to reset a password.
Select your startup volume ("Macintosh HD," unless you gave it a different name) if not already selected.
Select your username from the menu labeled Select the user account if not already selected.
Under Reset Home Directory Permissions and ACLs, click the Reset button.
Select
           ▹ Restart
from the menu bar.