DBTL, you are right I do have F lock. If I had realised the significance of that I would I would have F........................................................... .................
As for the drive letter. I am the victim of an MS 'conspiracy' and I am going to use F: as my OS drive - the letter will keep reminding me that Bill Gates has complete control over us. We are doomed!
Thanks for your input guys - much appreciated.
PPP