I think you can use jython script in Cache Refresh to pull+make lower case for UID attribute. Something like - Read sAMAccountName ( if that is the primary key in your backend AD ) - Run a loop - Convert them in LowerCase for attribute in attributes: attrName = StringHelper.toLowerCase(attribute.getName())

In this case my Primary key is set to UserPrincipalName. I haven't done a Jython script so pardon if I run a few sanity checks. I didn't put a ton of skill points into this haha. Would something like this work? > #update User Principalname > for attribute in attributes: > attrName = attribute.getName() > "userprincipalname" == StringHelper.toLowerCase(attrName)

You can take a look at your own Gluu Server. We shipped with sample codes inside there, you just need to put your classes and declaration according to your requirement. Hit 'Cache Refresh' tab from [Manage Custom Script](https://www.gluu.org/docs/admin-guide/configuration/#manage-custom-scripts) section. The idea of 'manage custom script' is to design and operate your Gluu Server according to organization's very own need.