If you are developing Android app using Kotlin then you might have come across this problem of Outdated Kotlin Runtime
I got this error when I updated Kotlin Plugin Version through Android Studio. It appears due to the different versions of Kotlin Runtime Library and Kotlin Plugin Version. Android Studio could not update the Kotlin Runtime Library on its own.
I had to update the Kotlin Runtime Library version manually.
Go to build.gradle file as shown in below image.
and the warning message I got
Outdated Kotlin Runtime
Your version of Kotlin runtime in ‘org.jetbrains.kotlin: kotlin-stdlib:1.1.51@jar’ library is 1.1.51, while plugin version is 1.2.20-release-Studio3.0-1.Runtime library should be updated to avoid compatibility problems.
I updated the Kotlin version from 1.1.5 to 1.2.20 and then started the gradle Sync. The warning message has gone now.
This solution worked for me. If you have come across any other solution please do let me know in comments section. I will update this post.
Some other useful toturial in Kotlin.
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