"There was a problem sending the command to the program." - Vista Help

fix windows 7 opening excel files in the same instance.

in regedit

rename ddeexec to ddeexec1 so it ignores data exchange

also add to command and default "%1" for xls and csv files

in excel options check the box to ignore other programs

"There was a problem sending the command to the program." - Vista Help:

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