Database Error - help!

[ry215]

I sometimes lost connection to my forum, sometimes it give me dead link when I click on any forum links. Here is what I got from my email everyday.
<b>
Database error in vBulletin 3.6.3:

Invalid SQL:

UPDATE d60299324session
SET lastactivity = 1163891368, location = '/forum/admincp/index.php?do=home',
loggedin = 2, inforum = 0, inthread = 0, incalendar = 0, badlocation = 0,
useragent = 'Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR
1.0.3705; .NET CLR 1.1.4322; Media Center PC 4.0; MEGAUPLOAD 1.0)', bypass = 0
WHERE sessionhash = 'a81494c7bff9b3c17a1f6a1265c4e799';

MySQL Error : Lost connection to MySQL server during query
Error Number : 2013
Date : Saturday, November 18th 2006 @ 06:09:28 PM
Script : http://www.tinhthoviet.com/forum/admincp/index.php?do=home
Referrer : http://www.tinhthoviet.com/forum/admincp/index.php
IP Address : xxxxxxxxx
Username : TTV
Classname : vb_database
</b>

I appreciate any helpful answer to this problem. Thanks.