When I click on the Excel shortcut icon, or type EXCEL in the Run dialogue box, the opening Excel screen just flashes on and off, and there is a Windows error sound. No workbook is opened at all and no error message. This is part of a MS Office 2000 installation, not standalone Excel, and all other Office products seem to be working ok. The easy answer would be to do a System Restore but because of a possible trojan infection, this had been turned off. I have followed the tips in Microsoft Knowledge Base Article - 280504 re startup problems but still no success. Anybody got any ideas on this one?

Sorry, I'm not hunting down that article to see what you did do. So, did you run Office Repair? What background tasks are running and are your available memory and GDI resources sufficient? What happens if you turn off the anti-virus so it doesn't run a pre-open check? Did you kill the xlstart template and create a new one? I don't use XP, but see no reason why you cannot do a registry restore without System Restore. Is the old 98/ME command scanreg /restore available in XP at system startup?

Try this. look for the Excel executable. It should be in C:\Program Files\Microsoft Office\Office (or something close to that) and click on the executable. If it works, go to Tools, Options and look for an option that says "Ignore Other Applications". If there is a checkmark next to that option, remove it and try the shortcuts again.