Question: Every time I use a firebase command this error occurs:

```
...\WEBRTCTest\FirebaseRTC> firebase use --add

Error: Invalid project id: \.

```

```
\WEBRTCTest\FirebaseRTC> firebase use --clear

Error: Invalid project id: \.

```

The error occured after I accidently run the command:

```
firebase use \

```

Prior to that all was working fine.

I tried to reinstall firebase-tools using npm and also re-cloning the example project from github.
Also tried to logout using `firebase logout` but it gives me the same error:

```
\WEBRTCTest\FirebaseRTC> firebase use --clear

Error: Invalid project id: \.

```

I´m thankful for any idea as i´m stuck right now.

Answer: 
Have you considered explicitly telling firebase what project to use?

```sh

# get list of projects
$ firebase projects:list

# add project id to most firebase CLI commands 
$ firebase <my command> --project=<my project ID>

```
I came a cross this problem and realized that there was another firebase.js file in the same folder as my project folder. When I deleted that firebase file, boom! it worked. Just check to see that there is no other firebase.js file that could be read from apart from the one you intend to be read from.