if you are using jstats for your joomla-site you probably have the same problem ...

a lot of visits from an ip address in this NetRange - You can do a lookup for the ip address in a whois database like http://cqcounter.com/whois/ and you'll see that the bot/spider who is bothering you is a service from microsoft.com

To get rid of all the visit counts you can try to insert the ip-address in your jstats_bot table and hope that jstats will recognise it the next time as a bot.

here is the sql code to insert the new bot

INSERT INTO `DATABASE`.`jos_jstats_bots` (
`bot_id` ,
`bot_string` ,
NULL , '65.55.11', 'microsoft.com'