The downgrade of UiPath.UiAutomation.Activities package to a lower version (for example from 25.10 to 24.10 or from 24.10 to 23.10) may break your UI activities. The only solution will be either to redo manually the UI activities in the lower version of UiPath.UiAutomation.Activities package, or use the actual new version of UiPath.UiAutomation.Activities package.
For the new version UiPath.UiAutomation.Activities package (25.10.2), you may reconsider using the latest STS version 2025.0.167 from https://download.uipath.com/UiPathStudioCloud.msi for Studio and Robot, but also upgrade the other project dependencies to a more recent version.
Notes:
System.Diagnostics.DiagnosticSource.8.0.0 is part of UiPath.OpenTelemetry.Contracts.2.5.17
UiPath.OpenTelemetry.Contracts.2.5.17 is part of UiPath.Telemetry.Client.2.5.17
The UiPath.Telemetry.Client is part of UiPath.UiAutomation.Activities and UiPath.Excel.Activities
Under UiPath.UiAutomation.Activities.25.10.2 is UiPath.Telemetry.Client.2.5.17
Under UiPath.Excel.Activities is UiPath.Telemetry.Client.2.3.3
UiPath.OpenTelemetry.Contracts.2.3.3 needs actually System.Diagnostics.DiagnosticSource.6.0.0 and not System.Diagnostics.DiagnosticSource.8.0.0
In conclusion, the issue occurs between the used versions of UiPath.UiAutomation.Activities package and UiPath.Excel.Activities (incompatible version of System.Diagnostics.DiagnosticSource.8.0.0 with System.Diagnostics.DiagnosticSource.6.0.0).