whats this error? can help me?

[critical]

Database error in vBulletin 2.2.8:
Invalid SQL:
SELECT
post.*,post.username AS postusername,post.ipaddress AS ip,user.*,userfield.*,icon.title as icontitle,icon.iconpath,
attachment.attachmentid,attachment.filename,attachment.visible AS attachmentvisible,attachment.counter
,avatar.avatarpath,NOT ISNULL(customavatar.avatardata) AS hascustomavatar,customavatar.dateline AS avatardateline
FROM post
LEFT JOIN icon ON icon.iconid=post.iconid
LEFT JOIN user ON user.userid=post.userid
LEFT JOIN userfield ON userfield.userid=user.userid
LEFT JOIN avatar ON avatar.avatarid=user.avatarid
LEFT JOIN customavatar ON customavatar.userid=user.userid
LEFT JOIN attachment ON attachment.attachmentid=post.attachmentid
WHERE post.postid IN (0,4018,4019,4020,4021,4045,4179,4182,4211,4212,4213,4215,4222,4245,4284,4285)
ORDER BY dateline
mysql error: Can't open file: 'attachment.MYD'. (errno: 145)
mysql error number: 1016
Date: Saturday 11th of January 2003 01:55:55 PM

[Steve Machol]

Error code 145: = Table was marked as crashed and should be repaired

Upload repair.php (it's in the 'extras' folder of the zip file) to your admin directory. Close your forums, then run it from your browser with this syntax:

http://www.yourdomain.com/forum/admin/repair.php?html=1&check=1

[Of course change the exact URL as appropriate for your forums.]

If everything reports 'Ok' then reopen your forums. If not, then run it again. The second time everything should report Ok. See if this fixes the problem.