Microsoft is yet to release stand-alone ISOs for the RTM bits of Windows 8.1, so your only option to update right now is to use the built-in Store link.
Lots of users, however, are provided with all kinds of errors, some of which block the installation process and restores the original Windows 8 configuration.
Windows 8.1 installation error 0x80004005 is one of the issues still causing headaches to many Windows 8 adopters, especially because Microsoft is yet to release a fix on this. The error shows up after the update is downloaded and the computer restarts for the first time.
Here’s what one of the affected users is writing:
“I have the same issue and went to far as to perform a clean install of Windows 8, apply all available Windows Updates and then tried to update to Windows 8.1 from the Store and am having this same issue in the same way I was having it before the clean install of Windows 8.”
Basically, the easiest way to fix this problem is to perform a clean install. Make sure you back up all your data, download the Windows 8.1 ISO and install the new operating system on an empty partition.
If you’re still planning to determine the cause of the issue, Dell’s support team is pointing users to an official Microsoft advisory claiming that the error occurs if “dynamic-link library files (.dll files) are not registered correctly or if there is a firewall between the computer and the Internet that does not allow HTTPS (SSL) connections.”
To fix this, launch a command prompt window with administrator privileges and run the following commands, one by one:
Reboot your computer and try to install Windows 8.1 once again.
Of course, make sure you drop us a line in the comment box below if one of these workarounds solved the issues for you or in case you’ve found a new way to deal with the error.