Weird file not found errors on Webmaster Tools

[tahiti]

Greetings all,

As referring to the subject, I am having a series of weird file-not-found error when I check with Google Webmaster Tool.

While running the website dianogsis tool (Dashboard > Diagnostics > Web crawl > Not found), the result shown that Google bot encounters hundreds of 404 error on my website. What's weird about this is that the website is quite an old static HTML site and I do not have those files (thus can't be found) on my hosting at all.

The URL with 404 errors are all filled with long funny variables that I don't even know where do they come from. Examples:

http://www.example.com/DI...%3Cbr%3E%3Cbr%3E%3C/td%3E%3C/tr%3E%3Ctr%3E%3Ctd%20background=
http://www.example.com/widgets...%3Cbr%3E%3Chr%3E%3Ca%20href=

Is there anyone who encounter the same problem here as well? If so, have you guys found out what cause this error and how to solve the problem?

The website was lived since year 2003 and it was ranking well on Google since early year 2005. Unfortunately its rank for many keyphrases are now displaced and I wonder does this error have anything to do with the ranking drop.

Thanks in advance for any help/advise given.

Cheers,
Tahit (will go there, soon! :))

[tedster]

First thing to say is that if your server is actually returning a 404 http header, then there probably isn't any major concern here. And it's very possible that you may never find the source of the urls.

These particular incorrect urls are very strange, and that's mostly why this thread is running as its own topic. But the basic subject of odd 404s in Webmaster Tools or in your server logs, has come up quite a bit, most recently in this thread:

Webmaster Tools Phantom 404's - where do they come from? [webmasterworld.com]

[tahiti]

I see, thanks a lot Tedster! Will further my reading at the mentioned thread.