apache搭建cgi出现的问题

[yopper_]

apache搭建cgi服务器：
linux下c编程的cgi文件放在cgi-bin目录下
html和js文件放在htdocs目录下

测试时报：
500 Internal Server Error
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.

error.log中：
C:/Program Files/Apache Software Foundation/Apache2.2/cgi-bin/a.cgi is not executable; ensure interpreted scripts have "#!" first line, referer: http://localhost:50080/Login.html
Bad file descriptor: don't know how to spawn child process: C:/Program Files/Apache Software Foundation/Apache2.2/cgi-bin/a.cgi, referer: http://localhost:50080/Login.html

不知何故，各位请帮忙！！！