Error - "Unexpected error on server associating the workflow" when publishing SharePoint Designer workflow. Also existing workflows "fail on start"

Question

As per title.

I noted that errors start occurring from 25 Sep onwards. Is this due to SharePoint CU?

I tried clearing the SharePoint Designer Cache below but is not helpful.

1. Delete all folders in the following directory in local: C:\Users\USER\AppData\Roaming\Microsoft\SharePoint Designer\ProxyAssemblyCache\
2. Delete the files in all folders in this directory in local: C:\Users\USER\AppData\Local\Microsoft\WebsiteCache\ don’t delete the folders, just delete the contents of the folders

Answer 1

Hi @Lai Keng NG ,

Thank you for posting in this community.

After installing the September patches, including KB5002624, workflow is getting error "failed on start". KB5002624 has a known workflow issue. Description of the security update for SharePoint Enterprise Server 2016: September 10, 2024 (KB5002624)

• To work around this issue, register the safe types in the Web.config file. You can look for event tag "c42q0" in ULS logs to find the blocked type. If the type and assembly are safe, add the type to the authorized list in the Web.config file. For example:

  <System.Workflow.ComponentModel.WorkflowCompiler>    <authorizedTypes>      <targetFx version="v4.0">         <authorizedType Assembly="Microsoft.SharePoint.WorkflowActions, Version=16.0.0.0, Culture=neutral, PublicKeyToken=null" Namespace="Microsoft.SharePoint.WorkflowActions.WithKey" TypeName="*" Authorized="True" />     </targetFx>    </authorizedTypes>

Threads similar to your question for your viewing pleasure:https://learn.microsoft.com/en-us/answers/questions/2077853/after-kb5002624-2010-workflow-is-getting-failed-on

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