How can I solve error code 805a0190 problem since I'm unable to access apps store with my Lumia 625. kindly give the procedure, i don't know how to update it to windows 10.

The Lumia 625 is not supported for Windows 10 Mobile and cannot be updated to it. There is no procedure to give.

Supported phones that can update.  Lumia 1520, 930, 640, 640XL, 730, 735, 830, 532, 535, 540, 635 1GB, 636 1GB, 638 1GB, 430, 435

Only way now is to update to Windows 10 mobile is using the OTC updater.

OTC updater is in this discussion

https://answers.microsoft.com/en-us/mobiledevices/forum/all/error-accessing-the-app-store-and-not-being-able/309d5e31-921c-45df-9d61-cf94c9bcbd1e

To start out clean without baggage, use the Windows Device Recovery Tool

https://support.microsoft.com/en-us/help/12379/windows-10-mobile-device-recovery-tool-faq

This will give you a clean start and a fresh install of 8.1

Do not use a backup when the phone restarts, still be on 8.1 so no apps will install.

You don't even have to add your MS account yet, just let it finish.

Then use the OTC updater, do not use any backups. check for updates, there will be more.

When all is finished updating add your MS account. Go to the store, menu top left, my library. Select which apps you want to install.

please help me to solve he error code 805ao190. i can't open my play store in lumia820.

error code 805a0190 for lumia 820. How can i solve it.

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