If you want to back up the IR codes that it's learned, do the following:
1) Open the registry editor (Start-->Run--> Type "regedit")
2) Navigate to the key:
HKEY_CURRENT_USER\Software\VB and VBA Program Settings\UIRT_IR
3) Make sure that key is selected (i.e. highlighted in blue by left-clicking on it on the left pane of regedit )
4) Select "Registry-->Export Registry File" and make sure that "Selected Branch" is selected
5) Save your "backup" file.
To Restore:
I think you would open the registry editor and select "Import Registry File", and open your backup file. WARNING--I have not tested this!! Messing with your registry file is dangerous etc. etc...