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#391
Sorry guitar looks like you'll have to install a 64bit OS mate perhaps replace the drive and get an OEM if the retail is too much. While you are at it it might be the chance to get a SSD and use the other dirve for backup or just transfer the data form the original drive to an external. The original drive will be good for a life saver if the new one goes south.
I found this. 64 bit - Application cannot access more than 4 GB on 64 bit processor - Super User
If you go with this option and personally I would make sure you align the SSD properly and use the optimise tutorial/s.
SSD Alignment < again personally I do this for all drives to make sure I don't miss the odd SSD
Optimize Windows 7[2]=Performance Maintenance < in my mind essential:)
Good luck and let us know how you go.
John