Login Problem in Ubuntu 16.04

[AnupamMitra]

Since yesterday night can't enter in my desktop o/s ubuntu 16.04 thogh I entered correct password. However, I can enter into Terminal by Alt+Ctrl+F2 wherein if I enter my password, it allow me to write/post.

[Perfect Storm]

Do you have nvidia card in your computer?

[AnupamMitra]

No, what I found is as under.
VGA compatible controller : Intel Corporation Device 1902 (rev 06).

[Perfect Storm]

Try reset the password, you can see how here: https://help.ubuntu.com/community/LostPassword

[AnupamMitra]

@Artificial Intelligence - I humbly suggest that it is not a problem of password. When I enter the password to log in, it shows that "failed to start session". Moreover, when intentionally I input wrong password, it shows "invalid password,...........". Kindly think again and give your valuable advice.

[Perfect Storm]

okay.

Try with:

sudo apt install --reinstall ubuntu-desktop
sudo apt install --reinstall ubuntu-session

[DuckHook]

@OP

Please describe your actions just prior to the problems. Did you do a no-no like:

sudo gedit

…or:

sudo nautilus

If so, you may have corrupted your /home directory or .Xauthority.

[AnupamMitra]

@Artificial Intelligence - Many many thanks Dear. This time I could enter to my system with your advice. I got back everything. Hats off. Regards.