Full Error Message:
“Error while creating new document. Error message: actionId cannot be blank”

-This error message can happen when generating a document and there is an issue with the document action or document action ID.

How to Resolve:
Typically this error message means there is a permission issue with the user trying to generate the document. You need to double check if all app users have access to Document Action object. You can check this by going to Setup > Security Controls > Sharing Settings > Document Action. Make sure it is not set to “Private” and instead set to “Public Read/Write.”