Why so red? IntelliJ seems to think every declaration/method cannot be found/resolved

Question

I just installed and re-installed IntelliJ. Every Java file is coming up RED. I checked the JDK; it is at 1.6.##. The maven clean install build worked just fine

Answer 1

I had the same problem after changing JDK from 1.6 to 1.7 in my pom.xml and setting Maven 3 path + JDK project settings to 1.7.

What did it for me was => File -> Invalidate Caches and Restart

PS: problem occured again, so i just reimported the full project after deleting the .idea folder and now it works fine as usual :)