[Solved]-IntelliJ IDEA - sbt plugin - 'Expression type Def.Setting[...] must conform DslEntry in sbt file'-scala

I simply installed the newest sbt version on my system and updated project/build.properties so it contains the new version number. This solved the issue for me. You might have to trigger a refresh in IntelliJ manually.

You can also try cutting and pasting everything in your build.sbt file to a word doc, importing your changes, and then pasting it back into the build.sbt file.

I closed and removed the project in IntelliJ, then, in my project folder, I removed the subfolders project/, target/ and .idea/. Then there were remaining only build.sbt and src/. Afterwards, in IntelliJ, I did: File -> New -> Project from existing sources -> import project from external model -> sbt.

This procedure has generated a new .idea Project file.

Expression type Def.Setting[String] must conform to DslEntry in SBT file has been gone now.

Hope this helps.

UPDATE 2018-11-17:

When shuffling with modules and projects in IntellIJ SBT, try replacing

lazy val root = (project in file("."))

with an always distinguished

lazy val root = Project(id="module_xyz", base = file("."))

In my case, the problem was solved this way! It occured from having multiple (project in file(".")) in different modules/build.sbt files belonging to the same IntelliJ SBT project. It seems to me that there can only be one (project in file(".")) in an IntelliJ SBT multi module project. So having many different Project(id="module_xyz", base = file(".")) can solve this.

I had the same issue. This solution worked me everytime. 1. Click on sbt tab of right side in IntelliJ Idea 2. Click on Refresh symbol

It will revalidate the Local cache and Gradle dependencies. That's it.