I check my website error log and found the following errors:

File does not exist: /home/user/public_html/"http://www.mysite.com/modules/khat/msg.wav/"

File does not exist: /home/user/public_html/modules/newbb/images/blank-a.gif

the msg.wav is there in the, but still has that error.

and I do not have the blank-a.gif file, and don't know what it's for. and there are a few other File does not exist.... but too many to list.

How do I eliminate these errors to improve the performance of my site?

/modules/newbb/images/blank-a.gif

That's top of my "404 - not found" list.

I've noticed that when REPLYING to some posts, the part of the page showing the previous posts has random red Xs all over the place. I wonder if THIS is the blank-a.gif? Right clicking on the images tells you nothing.