Someone trying to claim ownership of my site?

What else would these odd requests be for?

[MatthewHSE]

I got a couple 404's yesterday that look funny to me. Awhile back I did something with Google (can't remember why now) to establish ownership of my site by uploading a randomly-named file. These 404's look like kind of the same thing, only with Microsoft instead of Google, and this time I didn't initiate it. This makes me wonder if perhaps someone is trying to tell Microsoft that they own my site, or if some other type of badness is afoot.

Here are the requested pages:

http://www.example.com/5C5CD53D211A7024DCB344B423032A60.htm
http://www.example.com/AD7892597925054980D063ACC9601064.htm

The first one came in about 7:21 PM, second around 8:06. The UA was the same in both cases:

Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 1.0.3705)

The IP was also the same, 131.107.0.95, which resolves to tide525.microsoft.com. A few quick searches don't reveal any information on why they might be requesting files like those above.

What's going on here, and is it anything to be concerned about?

[bobothecat]

I just saw the same thing happen, Microsoft requesting an odd/non-existent file:

/8B0172D7774026BB0506D9B2C032A799.htm

They could be testing 404's... I recall Slurp/Yahoo did this for a while too.

It deffinitly doesn't look like it's anything to worry about,