Intellij: Not a valid project ID:

Question

I updated Intellij Idea to 2018.2.6

Now I can not start my Play-Project with a Play-Configuration - it gives me this:

[error] Not a valid project ID: myProject
[error] project myProject
[error] ^

I tried all of these proposals:

https://intellij-support.jetbrains.com/hc/en-us/community/posts/115000530510-SBT-Shell-Error-Not-a-valid-key-idea-shell?flash_digest=650678ba2e9ae36479f2c3e0ab460379a393d2ce

A plain SBT configuration works.

Answer 1

In my case, the reimporting of sbt project fixed the issue. This can be done by clicking on the "sbt" tab on the right pane, right-click on the project and selecting "Reimport sbt Project".

Answer 2

I could solve the problem:

• Close Project in Intellij.
• Delete .idea folder of the Project.
• Open the Project again.

Answer 3

Using IntelliJ Idea Ultimate 2020.2 none of the above worked for me.

I had to

• Delete the .idea folder
• Restart IntelliJ
• File -> Project Structure
• Create a new play module at the same location