I can't access my sdcard!!

[Tuhin_]

I recently updated my Micromax E313 to Android 5.1 from Android 4.4.2.
After the update, apps can't access my sd card.For example when I use a download manager to download files directly into sd card, it shows 'invalid path, index 0 size 0'.
When I try to send files to sd card from pc via xender over WiFi, it can send files to internal storage, but not to sd card.
Pls Help.
I can't copy via usb cable.
Here is a screeenshot from xender

 

[hang-the-9]

Why did you downgrade? Was this an official release you went to or a custom ROM? Did you check the card in a computer or another phone? If you look in the storage settings does it show the card there?

 

[Tuhin_]

Why did you downgrade? Was this an official release you went to or a custom ROM? Did you check the card in a computer or another phone? If you look in the storage settings does it show the card there?

I didn't downgrade. It was 4.4.2 at forst and I updated it to 5.1. This was an official release.
I can play the music or view images on sd card but when I try to copy soomething or download somerhing into sdcard, it shows permission required.

 

[hang-the-9]

For some reason I read your post as going from 5.1 to 4.4.2

Was the system rooted before the update started? You may need to check security settings on the device, and copying the SD card files out and formatting may be a good idea.

 

[Tuhin_]

For some reason I read your post as going from 5.1 to 4.4.2

Was the system rooted before the update started? You may need to check security settings on the device, and copying the SD card files out and formatting may be a good idea.

It was not rooted, and how can I change the security settings on the device?

 

[hang-the-9]

There is a forum post here they may help http/androidforums.com/threads/sd-card-write-permission-issue.893804/ It goes into quite a bit of details about permissions.