SSI exec command on IIS 7

I am trying to include the output of a perl script in an .shtml file via the
SSI command "exec cgi" but I keep getting a win32 error code 123. If I go to
/cgi-bin/RNDImage.pl the "Hello World" text is printed as it should be but
using just generates this error. I
know II7 is locked down by default and as I am new to both Vista and IIS 7 I
figure I am missing some config thing. Can anyone help me figure this out?

RE: SSI exec command on IIS 7

Can anyone please help, even just a suggestion at what to start looking at
that might cause this problem?

RE: SSI exec command on IIS 7

After digging around on google for a while more i ran across someone else who
had this issue on IIS 5. They had to add a leading "/" to the directory path.
I did that and now all is working.