first Flash your Windows Phone to factory setting (setting-about-reset) or hard reset it (when wp turn off hold down power button + volume down) and then if the flash success you can update your phone to 8.1. ps: your phone will update several time before getting the 8.1 update
How do I fix error code 805a8011 on my Windows phone?
Error code 805a8011 always appears when you are not signed in to your Microsoft account. It may also mean that you are not normally allowed to access the store. To fix this issue, check if your Microsoft account is added in addition to your phone. Go to Settings > Email and > Microsoft Account Profiles.
Why is my Windows Phone Store Not Working?
If you’re having trouble launching the Microsoft Store, you can try the following methods: Check for sign-in issues and make sure you’re signed in with a Microsoft account. Of course, make sure the latest Windows update is selected: Click Start, then select Settings > Update & Security > Windows Update > Check for Updates.
Does Windows Phone 8.1 still work?
After doing this, your Windows Phone 8.1 device should continue to work, but there will be no updates (including warnings) and device backup functions after this, but other basic services will be disabled, as described above.
Windows knows that most users experience problems as soon as their service packs are installed on their computer or when they try to install new software. Some Windows users encounter error code 800f020b when trying to install one or more updates.
If you are using firewall support, disable it until you install update builds or add the following Windows Update sites to the exclusion list. To work around Windows Update error 80072F8F on Windows Phone, set the correct date and time zone on your device. In the application list, click “Settings”.
Today, thousands of Windows Phone 8.1 buyers turned out to be cell phones complaining about error 80070020 when downloading apps and games. The Windows Phone Store is throwing error 80070020 which occurs when a user tries to download almost any app and there seems to be no official workaround available.
Ermias is a tech writer with a passion for helping people solve Windows problems. He loves to write and share his knowledge with others in the hope that they can benefit from it. He’s been writing about technology and software since he was in college, and has been an avid Microsoft fan ever since he first used Windows 95.