I exported a solution from a Dynamics 365 v8.2 instance. The solution contains a plug-in assembly with ten plug-ins and at least two steps registered for each plug-in. Several of the plug-in steps also have pre- and post-images defined for them.
In a Dynamics 365 v9 instance, I imported the solution and then published all customizations.
I then opened the v9 plug-in registration tool and saw that all plug-ins and steps were shown.
Later, I needed to update one of the plug-ins so I made the change in Visual Studio 2017, rebuilt the plug-in assembly and used the v9 plug-in registration tool to update the assembly. I was careful to make sure that I selected the checkbox to include all plug-in steps when updating the assembly.
After about 30 seconds, I started getting the feeling that something was wrong. Normally, updating a plug-in assembly only takes 5 seconds or so.
Finally, the message box appeared indicating that the plug-in assembly updated successfully.
Unfortunately, the v9 plug-in registration tool unregistered all plug-in steps... at least 20 of them!
Hopefully someone sees this and can avoid running into the same problem. When using the v9 plug-in registration tool, I would be sure that you have a backup of the plug-in assembly and all processing steps before updating an assembly. Otherwise, it might take you a while to put all the pieces back together.
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