Hi Bruce, I have now with your help solved this . For info the is %APPDATA% is the standard xp C:\documents and settings\userid\application data\ (there are some upper case letters due but that would be complex typing for me.) The problem seems to be although the user has write permission to this folder, Demeter doesn't try to create Its own folder (does this happen during a standard install for the installer?) so it seems when in startup it finds there is no %APPDATA%/Demeter folder to put the log in it gives up. Hence by first creating a Demeter folder in %APPDATA% folder, the program runs happily. Thanks for the help in figuring it out. Cheers Fred ted is short for sorted BTW. -- This e-mail and any attachments may contain confidential, copyright and or privileged material, and are for the use of the intended addressee only. If you are not the intended addressee or an authorised recipient of the addressee please notify us of receipt by returning the e-mail and do not use, copy, retain, distribute or disclose the information in or attached to the e-mail. Any opinions expressed within this e-mail are those of the individual and not necessarily of Diamond Light Source Ltd. Diamond Light Source Ltd. cannot guarantee that this e-mail or any attachments are free from viruses and we cannot accept liability for any damage which you may sustain as a result of software viruses which may be transmitted in or with the message. Diamond Light Source Limited (company no. 4375679). Registered in England and Wales with its registered office at Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom