Ok,lets try this steps:
<ol>
<li>Click <>Start</> <img title="Start button" src="http://support.microsoft.com/library/images/support/kbgraphics/Public/EN-US/VistaStartButton.jpg" alt="Start button" />, type services.msc in the <>Start Search</> box, and then click <>services.msc</> in the <>Programs</> list.</li>
<li>Double-click <>Background Intelligent Transfer Service</>.</li>
<li>In the <>Startup type</> box, click <>Manual</>, and then click <>Apply</>.</li>
<li>On the <>Log On</> tab, verify that the service is enabled in every hardware profile that is listed.
<>Note</> If the service is disabled in one or more hardware profiles, click the hardware profile, click <[b]>Enable</[b]>, and then click <[b]>Apply</[b]>.</li>
<li>On the <[b]>General</[b]> tab, click <[b]>Start</[b]>.</li>
</ol>
<[b]>Note</[b]> If BITS starts successfully, visit the Windows Update Web site or the Microsoft Update Web site to install updates. If BITS does not start successfully, go to Method 2.
<h3 id="tocHeadRef">Method 2: Rename the Windows Update Download folder</h3>
<ol>
<li>Click <[b]>Start <img title="Start button" src="http://support.microsoft.com/library/images/support/kbgraphics/Public/EN-US/VistaStartButton.jpg" alt="Start button" /></[b]>, type notepad in the <[b]>Start Search</[b]> box, and then click <[b]>notepad</[b]> in the <[b]>Programs</[b]> list.</li>
<li>Copy the following commands, and then paste them into the Notepad file.
<code>net stop wuauserv
CD %systemroot%\SoftwareDistribution
Ren Download Download.old
net start wuauserv</code>
</li>
<li>On the <[b]>File</[b]> menu, click <[b]>Save as</[b]>.</li>
<li>In the <[b]>File name</[b]> box, type rename.bat, and then click <[b]>All Files (*.*)</[b]> in the <[b]>Save as type</[b]> box.</li>
<li>Save the rename.bat file to the desktop.</li>
<li>Right-click the <[b]>rename.bat</[b]> file, and then click <[b]>Run as administrator</[b]>.
<div>
<div> <img title="User Account Coantrol permission" src="http://support.microsoft.com/library/images/support/kbgraphics/Public/EN-US/SecurityShield.jpg" alt="User Account Control permission" /> If you are prompted for an administrator password or for a confirmation, type the password, or click<[b]>Continue</[b]>.</div>
</div></li>
<li>Try to install updates again.</li>
</ol>