Why can't I download or install apps from sd-card?

[AC Question]

I have an Alcatel OT Idol mini (6012x), did a factory reset, fiddled with some system apps and now I cant download apps or install them from an sd-card.
When I get to the app management all the memory values on all the apps are 0.00b.
Settings>Storage is stuck on "Calculating" and if I try to uninstal an app I get "Untortunately Settings has stopped"
Trying to download an app from play store gets me an "error 491"
Trying to install an app from sd-card gets me "There's no aplication to open this file"
All previously instaled (stock) apps are working.

Any kind of help is welcome.

 

[tmbresley]

you cannot download an app "from" an sd card.all your sd card is for is for pictures you take and app you download too..apps that come factory with your phone cannot be sent to sd card..each time you download an app from play store ,you have to go to sttings,and move them..some you can and some you cant.but it will let you know..it also depends on how much gb card you have.alot og people dont look at the internal memory that comes with thier phone..the more app that come factoy with your phone,takes up alot of space..how mucg gb card do you have?

 

[tmbresley]

if you have alot of pics or messages stored in your phone,it will not let you do anything,i clear my recent calls and texts about every 15 or so

 

[Kocka77]

This problem has nothing to do with available memory. 16gb od sd-card are empty. It just doesn't let me download any app from playstore nor install a third party .apk file stored on an sd card. Sorry if my post title was a bit confusing.