Is the email possibly going to spam / junk mail / clutter / quarantine ? This is one possibility.
I had the user check that but to no avail. I am pretty sure something is not configured correctly since the last updated time in the subscription box above does not show that anything was updated. I have checked the error logs but nothing so far (not receiving an error message, just shooting in the dark). The user receives other dashboards so I am imagining it is something specific to this workbook, not sure why it works for other people though. No user level security is applied either.
The Backrounder processes are the one that sends out Subscriptions. If you do a search for the user account can you locate them at all? Unfortunately if you have a number of backgrounder processes then there would be several logs to look at. Also, I'm guessing is this Production? If so, can the issue be reproduced on a non-Production system if the same dashboard is published to it? Might make troubleshooting easier since there would be less activity to have to sift through.
I am able to replicate on the Non-Prod, that was a good idea as there are a lot less logs to go through. I did a search on the username and found this:
2018-07-16 07:15:58.434 -0700 (Default,username,,,370172,:single_subscription_notify,-) pool-4-thread-1 backgrounder: ERROR com.tableausoftware.model.workgroup.service.subscriptions.SubscriptionRunner - Could not send email for Subscription Id 14209 for User username Subject Last Week Census: Midnight
java.lang.RuntimeException: Failed to perform data condition evaluation...
Caused by: com.tableausoftware.nativeapi.dll.FederatedDataSourceException: DataServiceFailure
Unable to connect to the server "TABSERVER". Check that the server is running and that you have access privileges to the requested database.
This makes me believe that this is a data source error which is odd because it is using a published data source on the server that is used by many other workbooks. The TABSERVER that it couldn't connect to is the production server.
We do have the "Don't send if view is empty" for everyone on the subscription but everyone else is receiving it appropriately. I went ahead and unchecked it for the individual in question and it worked for her. Thank you for helping me get it working. I am still confused at why that would be an issue still since it shows it was fixed back in 10.3 and we are on 2018.1.
Glad to hear at least the user is able to get Subscriptions. For a deeper dive into the issue would strongly recommend opening a support case so the Tableau team can investigate further. When you open the case you're more than welcome to include this forum link but don't be surprised that we may ask you to reproduce the issue once more (possibly with logs in "DEBUG" mode in your non-Production environment) and collect a fresh set of Tableau Server log files.