why this error?
 

Startup Errors
Due to the following errors, the install/upgrade can not continue:

The version of includes/md5_sums_vbulletin.php is '4.1.11 Patch Level 2' which does not match the upgrade version of '4.1.11'. Have all of the '4.1.11' files been uploaded?

It looks like the file in question has not being overwritten with its counterpart from the vb package that you used to overwrite your forum files. Try to reupload it once again.

i did not overwrite i just uploaded new forum
and before this i uploaded version 4.1.10 and i face same error then i delete every file from server and reupload 4.1.11 patch level2 but still same error

So that file is already from the new package then? In that case ignore the error message and run the upgrader. But make sure to make a backup of your database first.

P.s. Is this a new install btw or are you upgrading your forum?

new isntallation,
and i have backup,

actually according to some problems my site was closed almost from 3 months, so its new installation now

Then ignore the error message and go ahead with the installation. I presume that you want to restore an older db backup. Is that correct? In that case, you don''t even need to run the installer. I take it that the config.php file is already edited with the db info. All you have to do is restore the db backup and then run the upgrader to bring the db up to date. If you will run into the same error again before you run the upgrader, simply ignore it.

why this happened ??

Unexpected Text:

<?xml version="1.0" encoding="windows-1252"?>
<?xml version="1.0" encoding="windows-1252"?>
<errors>
<error><![CDATA[<p>Database Error</p>]]></error>
<error_html><![CDATA[<p>Database error in vBulletin </p>
<p>Invalid SQL:

SELECT notice.noticeid, notice.persistent, notice.dismissible,
noticecriteria.criteriaid, noticecriteria.condition1,
noticecriteria.condition2, noticecriteria.condition3
FROM vbulletin_notice AS notice
LEFT JOIN vbulletin_noticecriteria AS noticecriteria USING(noticeid)
WHERE notice.active = 1
ORDER BY notice.displayorder, notice.title;<p>
<p>
<strong>MySQL Error</strong> : SELECT command denied to user 'admin_sam'@'boscgi3006.eigbox.net' for table 'vbulletin_notice'<br />
<strong>Error Number</strong> : 1142<br />
<strong>Request Date</strong> : Monday, May 14th 2012 @ 02:12:22 PM<br />
<strong>Error Date</strong> : Monday, May 14th 2012 @ 02:12:23 PM<br />
<strong>Script</strong> : http://forum.kiran-e-sehar.com/install/install.php<br />
<strong>Referrer</strong> : http://forum.kiran-e-sehar.com/install/install.php<br />
<strong>Classname</strong> : vB_Database<br />
<strong>MySQL Version</strong> : 5.0.91-log<br />
</p>]]></error_html>
</errors>

It seems like a permission issue. Make sure that the db user has full access/permissions to the db.