Ubuntu 16.04 freezes after login except with nomodeset

I just downloaded and installed Ubuntu 16.04.3 for my Sony Vaio Z Series laptop.

After the installation finished, a message asked me to restart. When I clicked on it, it just froze, so I shut down the laptop directly using the shutdown key.

Once I rebooted the laptop, I can log in a as guest without any problem (although it freezes when changing language or logout).

But I can't open my user account; I enter the password, click log in, then it freezes, although I still can move the cursor.

I executed apt-get install unity and dpkg-reconfigure, I've also tried apt-get remove --purge nvidia*.

I have the same problem with Ubuntu 17.04. I installed 16.04 and 17.04 twice, but still can't fix this issue.

I've also tried apt-get dist-upgrade, but it didn't help.

After setting the kernel boot parameters to quiet splash nomodeset, I can log in, but the problem is that with nomodeset the resolution is annoying.

How can I fix this problem?

I fixed the problem. Here's what I did exactly:

Since this happened after installing Ubuntu 16.04, and because nvidia drivers got messed up (as I was trying to solve the problem), I decided to reinstall Ubuntu again and try another solution.

1. I installed Ubuntu
2. With my new clean installation, I opened the GRUB menu by pressing the right shift key on reboot.
3. In the GRUB menu, I browsed with arrow keys to Ubuntu, press e to edit the boot parameters.
4. I browsed to the line starting with linux, and added nomodeset after quiet splash. Then pressed F10 to boot.
5. Now I could log in using my user account, I entered the password and got access to my desktop.
6. I searched for System Settings in the launcher, then Software & Updates, I set download from to Main Server. Then opened Additional Drivers tab, and checked one of the Nvidia (Proprietary, tested) drivers.
7. It took a very long time for Applying changes to finish (about an hour), and once it finished, I rebooted as normal (without nomodeset), and this time I could access to my user account.

Hope this helps others.

I had the same problem. The following commands worked for me:

sudo apt-get update
sudo apt-get install --reinstall ubuntu-desktop
sudo apt-get install unity

Hopefully it will work on your computer too.