Is it only failing on that one document?  Or for all documents?

Can you show me config of your convert document action please?

Hi Randall,

as Cassy Freeman‌ mentioned it would be good to know if it is just this document or if it affects other documents too.

I don't think the problem is the document but the SharePoint infrastructure. Document conversion utilizes the Word Automation Service which is a SharePoint service.

I would check the following:

• is the service still running correctly
  • to check this please go to Central Administration -> System Settings -> Manage services on server
  • 
• did the password of the service account running the word automation service expire?
• is there any log item in the SharePoint ULS log?

Hope this helps a bit.

Best regards

Enrico

Hi Enrico, thank you for the reply. It has happened for the one document only, the Word Automation Service is running properly. I wasn't able to find out any specific item in the ULS logs of help. The task had been working properly until this particular action. I'll check the passwords to be sure. 

Hi Cassey, thanks for your response. It has failed for this one document in particular. What do you mean by the config, you mean a portion of the XOML or just a screenshot of the action? Thanks again.

i meant of the action but if it is just affecting one document that is a different issue I would say.

I just experienced the exact same situation where one document converted and the other did not even though the link was valid. My situation consists of a triggered list workflow creating new items in their respective document libraries and converting them to pdf. To fix the issue, I created separate workflows in the document library to convert the document to pdf (triggers when a new document is created from my original list workflow). 

I also later realized that Nintex does not like all URLs created from multiple 'build string' operations. When I consolidated my URL to just one 'build string' operation, Nintex was able to recognize all links. Unfortunately, some of my original URLs worked and some didn't making pinpointing the issue difficult and time consuming.

I hope this helps.