Gilgamesh,
There are ways to read Excel's Command line arguments. Not sure what it
would give you, but may include a filename if .xls file is clicked.
Can't find a link, but I have seen such.
Try a Google.

NickHK

"Gilgamesh" wrote in message
...
I have an Auto_Open macro in a file in the XLStart directory that I want
to
behave differently if Excel is launched just by running the .exe or by
double clicking on an .xls file.
There has been a suggestion of checking for the book1.xls file but because
I
have files in the XLStart directory the book1.xls file does not get
created
when excel is launched.

Is there any way of telling programatically how excel of started? In my
old
unix days we could examine the parameter lines into the programe.

Thanks