Common Pitfalls in SharePoint Designer Custom Actions

I crafted a handful of custom workflow actions for SharePoint Designer recently and I noticed several recurrent errors:

• When you select a custom activity from the Actions drop-down, nothing happens

• Usual suspect: the class name and assembly reference do not match in ACTIONS file and DLL. Please check that your class reference in the Action tag in the ACTIONS file exactly matches your DLL full name.

• Not so usual suspect: SPD has a cached reference of your old DLL. Exit SPD, delete ApplicationDataMicrosoftWebSite Cache folder and restart SPD.

• Even less usual suspect: You've correctly placed the ACTIONS file and the activity DLL, but you haven't added an authorizedType element into your web application web.config file. Add the correct entry (you can check the whole process here) and try again.

• When you bind a property to a value, it doesn't get set

• Usual suspect: the demoted property name in your DLL and in ACTIONS file do not match. Please check that all your properties in the code exactly match the Parameters section elements in your ACTIONS file.

I hope that these simple advices save you valuable time. Happy programming in the WF world!