# Lambda Quad: Login loop. I can’t log in, but I’m entering correct password

## post by sabalaba on Dec 21, 2017

If you’re stuck at this screen and every time you attempt to sign in, Ubuntu pauses for a moment, then acts as if you’d typed the wrong password, you’re in a “login loop.” There are a few potential solutions to this issue:

**SOLUTION #1: REINSTALL NVIDIA DRIVERS**  
The easiest way to do this is to reinstall Lambda Stack, which includes NVIDIA’s GPU driver. At the login screen you’re stuck on, press CTRL+Alt+F1; this will open up a terminal. Now, enter the following command:

```
LAMBDA_REPO=$(mktemp) && 
wget -O${LAMBDA_REPO} https://lambdal.com/static/files/lambda-stack-repo.deb && 
sudo dpkg -i ${LAMBDA_REPO} && rm -f ${LAMBDA_REPO} && 
sudo apt-get update && sudo apt-get install -y lambda-stack-cuda
```

Now, reboot the machine.

**SOLUTION #2: DISABLE SECURE BOOT**  
This is a UEFI (replacement for BIOS) setting that breaks NVIDIA’s GPU drivers. [Follow instructions here to disable Secure Boot](https://deeptalk.lambda.ai/t/how-to-disable-secure-boot/392). You should now be able to log in.

## post by Sagubaja on Jan 4, 2018

Im having the sme truble with the tensorBook but it doesnt work, can tou please help me

## post by sabalaba on Jan 4, 2018

What is the contents of the error file, can you please post a screenshot here of this command’s output?

```
cat /var/log/nvidia-installer.log
```

## post by Sagubaja on Jan 5, 2018

Here is what pops up when i enter the comand

## post by Sagubaja on Jan 8, 2018

Can you Gide me to fix this, I haven’t been able to use my tensor book at all

## post by sabalaba on Jan 9, 2018

Hi Sagubaja, we’ve sent you an email from our official support team who will be looking into this for you!

## post by dkermany on Jan 16, 2018

Hello,

I have a Lambda Quad and this fix does not work for me. There appears to be an error during driver installation. Error log attached below.

## post by sabalaba on Jan 16, 2018

Hey! Can you try installing from the public repos instead:

```bash
LAMBDA_REPO=$(mktemp) && 
wget -O${LAMBDA_REPO} https://lambdal.com/static/files/lambda-stack-repo.deb && 
sudo dpkg -i ${LAMBDA_REPO} && rm -f ${LAMBDA_REPO} && 
sudo apt-get update && sudo apt-get install -y lambda-stack-cuda
```

Let me know if that helps [@dkermany](https://deeptalk.lambda.ai/u/dkermany)

## post by dkermany on Jan 16, 2018

That did the trick. Thanks!