> For the complete documentation index, see [llms.txt](https://docs.rmhpos.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.rmhpos.com/releases/old/3-9-11.md).

# 3.9.11

Release Date: August 16, 2021

## **Store Manager and POS**

### Prevent changes to the unit of measure in POS

Starting with release 3.9.11, stores can prevent the unit of measure from being changed at the register by selecting the **Do not allow to edit Unit of Measure on Inventory Tab** option on the **Extended Properties** tab:

<div align="left"><figure><img src="https://2921455087-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fjgsd9U4TRO2qgcIBegi7%2Fuploads%2FdIRM2JZpfVUkuG2H2fcv%2FRMH-store-item-inventory-ext-prop-uom.png?alt=media&amp;token=7b5c27ce-e189-4f59-a011-a09a09fa0792" alt=""><figcaption></figcaption></figure></div>

### Display WAM information on POS login screen

Starting with release 3.9.11, for UK customers only, the login screen for POS will now display the customer's WAM certification number, the file name of the DLL (RetailHero.POS.WAM.UK.DLL) used to manage WAM functionality for UK customers, and the checksum used to check for errors in the transmission or storage of data in Store Manager and POS.


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