<p>When trying to sign in to MSN messenger, a popup appeared saying that I needed to upgrade to the new version. When I tried to download it, it says it was not able to install and it gives the error message: hr:0x80070643 . I looked ALL over the internet for solutions and tried for AT LEAST an hour and a half trying all the solutions, but I couldn’t figure it out. </p>
<p>I also heard that error message has something to do with Windows Update, but my Windows Update always fails when I try to update.</p>
<p>Please don’t say “Go see a computer specialist” because I don’t want to have to pay 50-100 dollars for them to look at my computer.</p>
<p>If you know what I should do, lemme know please! I just wanna talk to some international friends via MSN/Windows Live Messenger!</p>
<p>643 is Windows Installer error. I’m pretty sure it has something to do with your Windows (Automatic) Updater (which you said isn’t working). Fix that and you fix your problem.</p>