I can not create or open worlds , either survival or creative. not old, infinite or plane

I get the same error (worldError.IO) on the Windows 10 edition, which seems to be the same codebase as the pocket edition.

I get same error on same tablet:
When I try to create world on my tablet, i get an error "worldError.IO". Folder with a world map have a strange name like "HVkAAJc-AAA=", and in LOG file there is only string
"2015/07/31-13:35:46.518118 549d7218 MANIFEST write: IO error: /mnt/sdcard/games/com.mojang/minecraftWorlds/HVkAAJc-AAA=/db: Bad file number"
Tablet is a cheap 7" device with Android 4.4.2 based on ATM7021 processor (http://www.actions-semi.com/en/productview.aspx?id=127)

result of world creating

strange wold folder names. both of them is result of creating world named "My World"

Thank you

I think that it is a continuation of bugs:
7851 (https://bugs.mojang.com/browse/MCPE-7851),
8580 (https://bugs.mojang.com/browse/MCPE-8580),
9013 (https://bugs.mojang.com/browse/MCPE-9013),
9023 (https://bugs.mojang.com/browse/MCPE-9023),
9178 (https://bugs.mojang.com/browse/MCPE-9178)

and so on (https://bugs.mojang.com/browse/MCPE-8580?jql=project%20%3D%20MCPE%20AND%20text%20~%20%22Bad%20file%20number%22%20ORDER%20BY%20created%20DESC)

Anything about "Bad File Number" can be found in this issue MCPE-8383, you can comment on it.

I'm not sure why this Bug was closed, since it is not a duplicate of MCPE-7623. It is an entirely different error and doesn't even mention "Bad File Number".

Linking to MCPE-8383, since the same reporter, commented that issue. My bad René.