Custom Webpart: Type not found or not registered as safe!

Question

I'm trying to implement this web part concept provided by Microsoft in our SP2013 environment using VS2012.

MSDN SPDataQuery Class Example

I've created a solution in VS2012 and verified that the proper SafeControls are present in the Package Manifest. I even copied them into the web.config as well. The solution deploys and activates fine to the GAC. However whenever I insert it into a web part page, I keep getting the "A Web Part or Web Form Control on this Page cannot be displayed or imported. The type could not be found or it is not registered as safe." error.

I have spent hours on Google, etc., and feel I've tried everything. I even rebuilt it to make sure I have not changed any names along the way.

Desperately need some help to get this working! Any suggestions are appreciated!

Thanks! Josh

Answer 1

I realize that you said you hadn't changed the names of anything, but there is another place to check for possible incorrect references:

I ran into the "type is not registered as safe" problem too, and it had to do with me changing the namespace and name of the web part. I thought I had accounted for the changes everywhere, but then discovered that there is a hidden .spdata file for the web part (in the same directory) that also contains namespace and class references. It was referring to the old names.

Once I updated the .spdata file to use the correct namespace and class name, everything deployed and worked as intended. Note: Do not include the class name in the Namespace attribute... sounds obvious now, but I included the full [namespace].[class name] there, and couldn't figure out for the longest time why it still wasn't working.

Hope this helps someone.

Answer 2

Check your assembly version from GAC with the web.config entry and with control registered. If they are mismatched then you need update web.config with the latest version of your assembly. Or try using assembly binding redirect as

  <dependentAssembly>
        <assemblyIdentity name="AssemblyName"
                          publicKeyToken="32ab4ba45e0a69a1"
                          culture="neutral" />
        <bindingRedirect oldVersion="1.0.0.1"
                         newVersion="2.0.0.0"/>
     </dependentAssembly>
  </assemblyBinding>

Please let me know if that works or if you have same versions in all the places.