try adding the culture en-US into the web.config:

<globalization requestEncoding="utf-8" responseEncoding="utf-8" culture="en-US" uiCulture="en-US" />

hth

Hi Trent,

go to /umbraco/config/lang and copy en.xml to us.xml. Open us.xml with an editor of your trust and change:

<language alias="en" intName="English (uk)" localName="English" lcid="" culture="en-GB">

into

<language alias="us" intName="English (us)" localName="English" lcid="" culture="en-US">

and save. Now you can go to User section open your user and select Language English (us). You will get US date format in Umbraco back office.

HTH

that did work. Thank you.

But it did kinda break the tinymce editor

TinyMCE: Error loading language 'us'. Please download language pack from tinymce.moxiecode.com

any ideas

Trent

@Trent, I followed Immo's instructions but instead of creating a new file I just changed the existing (en.xml) one from

<language alias="en" intName="English (uk)" localName="English" lcid="" culture="en-GB">

to

<language alias="en" intName="English (us)" localName="English" lcid="" culture="en-US">

It fixed the date issue, and haven't noticed any problems.

-Sean

Hi Trent,

I think the way from Sean is much better and avoid the problems with TinyMCE3.

For the case you need both en-US and en-GB languages you need to extend TinyMCE3 with the "us" Language. For this you need to copy and modify from en*.js to us*.js:

/umbraco_client/tinymce3/langs/us.js
/umbraco_client/tinymce3/themes/umbraco/langs/us.js
/umbraco_client/tinymce3/themes/umbraco/langs/us_dlg.js
/umbraco_client/tinymce3/plugins/table/langs/us_dlg.js
/umbraco_client/tinymce3/plugins/paste/langs/us_dlg.js
/umbraco_client/tinymce3/plugins/media/langs/us_dlg.js
/umbraco_client/tinymce3/plugins/advhr/langs/us_dlg.js
/umbraco_client/tinymce3/plugins/advimage/langs/us_dlg.js
/umbraco_client/tinymce3/plugins/advlink/langs/us_dlg.js

In each file you have to update language reference at the begin from en to us e.g. in tinymce3/langs/us.js.
from:

tinyMCE.addI18n({en:{

to:

tinyMCE.addI18n({us:{

This is also the case for extending of Umbraco back office UI for an additional language.

HTH, Immo

Hmmm, I know this topic was last touched last year, but I can't seem to get this to work -- we have a Date Picker field that is displaying Feb 3rd as 2012-02-03.  We would like this to say 02/03/2012 for our U.S. users.

I copied the /umbraco/config/lang/en.xml file to us.xml and made the change as suggested. I did indeed find this new "language" in my user record, which I updated, but the date format has not changed in our Date Picker field. (I did notice that the "Created" publish-status dates in the "Properties" tab did change, so this is at least half a victory for us!)

Thanks!

OK quick followup on somethin weird - After changing my admin user's language from English (UK) to English (US), it seems that my styles selector in the TinyMCE editor has an extraneous, bogus entry in it.  We usually keep just H3 and H4 styles defined in a special "CMS" stylesheet. However with the language changed, I now see a new option in this selection as follows:

{#umbraco.style_select}

If I change my user's language back to UK english, this weird CSS item goes away. I put it back to US english and it reappeared.

I would love to see more consistency in how these dates are rendered across the back-office UI in a future release! (perhaps with a single setting somewhere, out of the box.)

Thanks!

Any progress on this? We're stuck with a seriously buggy TinyMCE, as I noted here: http://our.umbraco.org/forum/using/ui-questions/29038-Change-Date-Format-in-Properties-Tab-(TinyMCE-bug)

Did the change to en.xml and most looks good.  However, date pickers show their results as yyyy-mm-dd.  Anyway to change that format?

Thanks! This solved my problem too.

Hello?  Anyone figure out how to fix the date display in a date picker?

Try my solution at http://our.umbraco.org/forum/developers/extending-umbraco/8268-Change-date-picker-format-in-Umbraco?p=1#comment166799

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