That is a bit difficult, not knowing what you have done so far.
- Have you edited httpd.conf, so your Apache knows what to do with cgi-scripts? If not check that file, usually you only have to uncomment a line or two.
- Is your cgi-script within a directory that has the permission to execute cgi-scripts (usually cgi-bin)? If not move the script or edit httpd.conf accordingly.
- Does your script have a she bang line? If not write #!C:\path\to\perl.exe as the first line into your script.
- Does your script print everything it needs to print, especially the Content-type header? This is a very frequent error when you don't use CGI;.
- Perhaps there are other errors while running the script, before it creates any output, check your Apaches error.log to find those.
I hope this helps to narrow the problem down or even solve it.