Dependency Version Issue using in library and in Process

I am using UiPath.System.Activities version 19.4.0 in library and version 20.10.6 in Process. when i impost package of library then process shows below error:

Error ERROR Validation Error System.MissiError ERROR Validation Error System.MissingMethodException: Method not found: ‘Void UiPath.Core.Activities.LogMessage.set_Level(UiPath.Core.Activities.CurentLogLevel)’

do I need to use same version of UiPath.System.Activities dependency in Library and Process.

If we use lower version of any dependency in library then it should not create problem with higher version of same dependency in Process.

Please help me on this on urgent basis.


In your library, make sure the UiPath.System.Activities dependency is set to “lowest applicable version” - this means when used in your process, the newer version will override the older version.

Its already selected Lowest Applicable Version. I am using lower version in Library and higher version in Process.

When I import package of library in process then it gives that error but when I make same version of UiPath.System.Activities in library then that error removes. We can not upgrade system.activities version in library as old processes are using this library with lower version.

Please suggest what should I do to overcome this issue.

In your Process, mouse over the Library on the Project tab and see if it says it resolved to the higher version.

Yes it says higher version resolved but that error comes

Have you tried other versions of System.Activities in your process? Could just be a bug specifically with 20.10.6

thats the issue i can not upgrade the system.actvities version in my processes for now as it build 3 years ago and it can be issue in existing processes.