an easy answer for this.
Those two errors are the same and they point to an error with the Windows Installer. But if you read the discussion in the link below you will find the original poster tried many options until he found his own;
His problem dated back to when he shut down his computer, then attempted to shut down a printer which failed to shut down, so he just unplugged it. In the meantime HP had offered updates which also failed and he ended up uninstalling the printer software then reinstalling. After that, Windows Updates worked perfectly.
Any strange happenings on this system since Windows Updates last worked?
I'm experiencing problems with Windows Update. My system is Vista SP 2. My updates have been failures since April 21, 2012. The Windows update screen shows the error codes as 641 and 80070641. The Windows Update icon is continually on the taskbar. The shutdown icon continually has an icon within it for installs updates and then shutdowns the computer. Can anyone help correct problem?
Thanks for your help.