Warning with guestbook....

Hi,
I have installed your guestbook at http://mrsahaf.com/GB2/
after i put in a message it gives me this warning:

Warning: unlink(index.html) [function.unlink]: Permission denied in /home/mrsahaf/public_html/GB2/lib/add.class.php on line 80
Guestbook
Thank you for signing the guestbook.

Your entry was added successfully! You should be transfered back to the guestbook in 2 seconds.

Why is that? What does that warning mean?

Is there any way I can first see every message before it gets posted?
Eg:
I approve every message before it goes "live"

This way I will avoid "asdfasgag" "123523" "testing123" etc.
Kindly reply,
-Ryan
r@jumac.com

can u help me:

Database Error
--------------------------------------------------------------------------------

MySQL Error : Database Error
Error Number: 1046 No Database Selected
Date : Tue, April 22, 2003 01:17:16
IP : 212.78.204.32
Browser : Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; DigExt)
Referer :
PHP Version : 4.1.0
OS : Linux
Server : Apache/1.3.27 (Unix)
Server Name : php-uk.tmm.lyceu.net

Hello ProblemGuy,

You could try the following:

Login with a ftp program to the server and right-click with the mouse on the map public and tmp, then change attributes from 750 to 777.