Thank you for your answer Madeline. Apparently history.dat is contained in C:\Documents and Settings\<Windows login/user name>\Application Data\Mozilla\.

I can't seem to find the 'application data' folder on my pc. I was looking for it the other day too. Could it be hidden?

The missus lets other people use the pc, and I've got a feeling that some unsafe sites are being visited, as my pc has developed a quite peculiar problem. I do have a good ghost copy of my HDD, if I can't get sorted, but I really want to get to the root of the problem, rather than just deal with the symptoms.

Any advice on how to find 'application data'?, a search brings up nothing.

Cheers Mugsy