Incorrect presentation of military dates (day/month/year)

Thanks for your response.

I never had a problem with Yosemite - just since I switched to El Capitan. My problem lies with QuickBooks. QB accepts the correct date format in my registers when entering, for example, 13 Dec 15 (13/12/15) up through the end of the month (31/12/15). When I enter a date prior to the 12th (since there are only 12 months) it inverts the day/date. It accepts the typed entry, for example 2/12/15 as 2 Dec 15, but posts and orders the date as 12 Feb 15. I have a forum question with Intuit about QB, but no answers yet.

The reason I suspect El Capitan may be causing a problem is that it just started. Plus the strange appearance in System preferences. The languages & regions page shows the correct order that I have selected i.e, 29 Jan 2016. When I close that page and go back to the date/time preference page, it shows 1/29/2016.

I've checked in Excel, selecting a cell to display the date as 14/3/01 and it properly displays 6 Jan as 6/01/16. Is it possible that this anomaly on the date/time page is causing a problem in QB?

The main problem now is that, at tax time, my printed report showing salary for the quarter picks up pay after the 11th of the month; but does not show any pay done earlier (i.e., pay on 2 Dec shows up as a pay made on 12 Feb and not on the quarterly report.)

I appreciate your help.

My point is not how to set the dates to the d/m/y format. They have been set that way for many, many years. The one visible issue is that with the date format set in languages & regions to d/m/y, the visible date in date/time is NOT what I set. In other words, it displays m/d/y. Why?

I just spent two hours on the phone with tech support and product developers with Quick Books. The issue, apparently, is that QB does not support date formats other than m/d/y. Having said that, however, I have used QB with my format of d/m/y for 12 years. It has not been a problem and all of my business files going back 12 years show d/m/y. The problem surfaced the first time I opened Quick Books after switching to El Capitan.

So far, the only resolution offered by Quick Books is to switch back to Yosemite. Before I even think about that, however, I want to be sure there is not some small glitch in El Capitan that has corrupted the display of some dates in QB. After all, it has worked successfully for 12 years.

Quick Books has said they will introduce my suggestion to support d/m/y as an option for future releases of QB. In the interim, however, my files are now messed up since entries made with d/m/y for dates between the 1st and the 12th of the month are placed backwards in the files into the months corresponding to the days I enter. All entries from the 13th of the month onward are shown and placed correctly in Quick Books. I plan on making no more entries into QB and hope that some patch can be introduced to fix the problem. If that happens, I hope to be able to go back to a saved version prior to when I switched to El Capitan and re-enter those transactions.

I appreciate your efforts in helping me resolve this issue.