There is no active transaction. This error is usually caused by custom plug-ins that ignore errors from service calls and continue processing

Hi guys,

Last friday I uploaded a custom plug-in and now my users are telling me that they get the error "There is no active transaction. This error is usually caused by custom plug-ins that ignore errors from service calls and continue processing" every time they try to Qualify a Lead.

I already unregistered the plug-in, but they still cannot Qualify and keep getting the error. How can I check which plug-in/step is causing the issue please?

Kind regards,
Raúl