Couldn't take screenshot on Lumia 520

[sharukh_shaikh7]

I was unable to take screenshot..Its giving error couldn't take screenshot..After some research I found that the filename of screenshot was being saved with same name as previous screenshot..as soon as I changed the name in file manager I was able to take screenshot...therefore I've to rename screenshot every time I want to take another one...pls help if you know fix for this issue