Hi Erik,
On an "unknown sender" there is a little more that comes into play here. Microsoft has documented the case creation and all the details on what to set and what happens here:
https://www.microsoft.com/en-us/dynamics/crm-customer-center/automatically-create-a-case-from-an-email.aspx
See step 6 for an important table (you will see after expanding the "Specify conditions for email to case creation").
Also, as I was answering this I thought of another approach you could do on assigning the case to a specific user / team. Microsoft introduced Routing Rule Sets that you should be able to utilize to accomplish what you need to do to route the case.
Overall you should be able to do the following to complete what you are looking to do:
1. Create your case creation rule that will create the cases from the email that is received. The "queue" would be tied to the queue you created for the email that the cases are received. Here it is "Email Support" as an example:
a. You will see I selected to automatically create cases for unknown senders
b. Currently no other rules / conditions are in place. If you needed to add record creation and update details then there is a lot that can be done there.
2. You will need to make sure that whomever is setup to own this rule has the checkbox set to automatically create records in Microsoft Dynamics CRM will create a contact.
At this point after this rule is activated and an email comes into that mailbox it will create the case and if there is no customer / contact associated with the email address of the person who sent the email it will create a Contact in the system and assign the case to that contact. Note, no account will exist in this situation, only a Contact.
Now we can create a routing rule set to handle the routing of these cases after they are created. This provides a lot of flexibility without the workflow as I had answered before. You can setup different rules within the routing ruleset to determine where the case is assigned (either to a queue or a user / team). It is really a nice capability. Only 1 routing rule set can be active at a time... You will find this on the Service Management page under Settings.
3. Create the Routing Rule set and name and put in description.
4. In the rule items you can define rules that will match your needs and then you can select where the case should be assigned by the rule.
5. You should be able to use these rules to look at your cases that are created and decide who the owner of the case should be and just put that in the Route To section. If you have no real rules and they all should route to the same person then you can just setup the Route To with no rule details.
With the setup here you should be able to remove the workflow we had discussed when I answered before as this provides more functionality / capabilities.
Thanks much,
