There was an article about compatibility mode for win98 many moons ago in PCA magazine(April 1999 page 86) if anyone has a copy. It sometimes happened to my O/S and I think I used to set the registry back to a date when it was working alright, you can try that. If I remember rightly it also slows your system down.
Thanks for the replies, it seems that the older of my two hard drives was causing the issue as it would no longer run in LBA mode, removing the drive has sorted the problem, it is quite old & is now pursuing a new career as a paper weight.
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