Here's the log
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Executing Gradle task: eclipse
Build info: MCreator 2020.2.14217, 1.14.4, 64-bit, 24524 MB, Windows 10, JVM 1.8.0_232, JAVA_HOME: J:\MCreator\jdk
> Configure project :
New Dep: net.minecraftforge:forge:1.14.4-28.2.3_mapped_snapshot_20190719-1.14.3
FAILURE: Build failed with an exception.
* What went wrong:
A problem occurred configuring root project 'wkspaceformcc'.
> Invalid patcher dependency: net.minecraftforge:forge:1.14.4-28.2.3:userdev
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 5s
BUILD FAILED
Task completed in 5716 milliseconds
solved
I just clean my files in users, the problems solved