Click Month(start_date) and select show missing values. Give it a try
No Guyz Its not working.
Curious why the 'show missing values' would not work. Please post up a packaged workbook, and if necessary Anonymize your Tableau Package Data for Sharing so we can help further.
Else, the only other thing I could think of, is you could create a second data source with all the months then blend on your primary source. Use the new data source dimension for months in your viz then any other fields from your primary you need to show.
I ran into a similar problem. The way I got around it was to populate an arbitrary filler value for months that did not exist in my data set. I would only do it for the last month though.
I would then do what everyone else is suggesting and use the "missing values" option.
Hope this helps,
I attached a test workbook.
Original (without any settings),
Users Jan May B 1 1
When "Show missing values" is checked on for month(start_date),
Users Jan Feb Mar Apr May B 1 1
When "Analysis -> Table Layout -> Show Empty Columns is checked on,
Users Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov B 1 1
If this doesn't work for you, just as Danial wrote, please post up a package workbook if possible.
show months.twbx 11.6 KB