If you receive the following error when you try to update Windows Phone 7, this article may help you resolve the issue.
There was an error while trying to update your device with the latest software. Please try again.
The timer ran out on what we were trying to do.
To see if there’s more information about this error, click Web Help.
ERROR CODE 800705B4
In such a scenario, Microsoft KB2518812 recommends that you sync your phone’s media content with your computer using Zune and then temporarily remove media from your phone.
If the update is now successful, you can sync your media back to your phone.
If not, remove a few apps and then try the update again.
If it works now, fine! If not, remove a few games instead and then try the update again.
If it works great!
The KB article however does not have an answer, what to do if it still doesn’t work even after removing games!
Read: Windows Phone Update Error codes with solutions.