Can i still Install the Update Advisor On a Windows 8.1 Mobile Phone

[Breno Rocha]

My mom uses her old Lumia 640 XL as a appointment book, and, recently, after a problem in the SD cards she lost most of her apps.

As the Windows 8.1 appstore was closed in a while ago, they can't be re-install. So i am trying to update the phone to Win 10 mobile. But for that i needed the appstore.

So i tried to install it manualy, I already have the XAP file on my pc, but the Local installer in the app store doesn't seem to find it.

There is something i can try?

 

[gmoore114]

The same thing will eventually happen to the store for Windows 10 phones.
You should not use the SD card for apps to prevent this from happening again. Use the SD card for only pictures, music and videos. Get all that done to a freshly formatted SD card you trust. Remove the card and set it aside till done.
Two steps:
Use the Windows device recovery tool to clean the phone and start off with a clean 8.1 phone. You do not have to enter account info when the phone restarts and never restore from a backup.
Then use the OTC updater to update the phone to 10.

WDRT https://support.microsoft.com/en-us/help/12379/windows-10-mobile-device-recovery-tool-faq
OTC updater https://www.microsoft.com/en-us/download/details.aspx?id=56726

After the WDRT go to the store and see that the apps get installed, then delete the ones that will not be available in 10.
After the OTC updater go to the store and see that all apps get installed. The phone will have system updates to install. See what is going on there in settings, phone updates. When all is done delete the apps you will not use, install the SD card, add the MS account to the phone.
Go to the store, menu top left, my library and install the apps you need.

You will have used less than 4.5GB of phone storage, plenty of room left for phone operation

See the instructions on the OTC updater page for install instructions and the readme file for requirements. The phone has to be in the airplane mode when you use the updater.

Make sure you have reset protection turned off before you start.