Thanks NickHK,

Yes, all saving to the same folder and maximum path+filename
combination coming out at around 150 characters.

However, this does appear to be related to that chestnut because if I
move the files up the directory tree nearer to the root the problem
dissappears!

There is also some wierd link with Outlook regarding manual saves. If
Outlook is closed manual saves work fine, if its open one or two of the
longer filename workbooks crash to the 'Send Error Report' dialog. Then
I have to kill the EXCEL.EXE process in Task Manager.

The client Uses Lotus Notes so I can probably get away with an entry in
the trouble-shooting section of the manual regarding long path+filename
combinations.

Thanks for your help chaps.

Kind regards,
NickH