How to open excel workbooks in SAME instance of Excel

[montadmail]

I have Excel 2003 with Windows XP.

From the File Explorer, every time I double click on a .XLS file, it

opens in a separate instance of Excel. This is a problem when
working on multiple workbooks, because linking and copying becomes
cumbersome.

What settings (File Explorer, Excel, or Registry) do I need to change
in order for all files to open in the same instance of Excel?

Thanks,
AABob

 

[Guest]

Select Tools|Options -> General (Tab) and uncheck "Ignore other applications"

 

[Jim Rech]

I believe the file associations need to be fixed. From Start->Run enter
"Excel.exe /regserver" (no quotes, there is a space before the slash).