Hi,
for a start (and given you work with Linux), open a teminal and type

tail -f /var/log/httpd/error_log
[download]

or wherever Apache logs to on your machine.
Then reload your cgi in the browser.
You should now see the error message you normaly see when using command line scripts.

Also, as Corion already pointed out, htdocs is usually the DocumentRoot of your Apache server, so you need to start your absolute path after the htdocs (in your case probably <img src="/test/DailyReport.jpg">
Regards,
svenXY