This is making me crazy...
I have two SharePoint 2013 farms, one for testing and one for production. The setup of them is nearly identical.
I have a lookup field in a custom list, and it includes some other values from the lookup list. These value fields are referenced in the format "Lookup List:Lookup Value".
On one server, the internal name for that field has "x003A" in place of the colon. However, when I create the same field on the other server, it creates it using "x003a" in the internal name, with a lower case "a" in the hex value instead of upper case "A".
This causes me problems because I am using SSRS to report data from the list, and the query it generates is case sensitive and it errors because it doesn't find the field in the list - due to the difference in case.
Any ideas about what would cause this or how to change it? From what I understand, I cannot change the internal name of a field once it is created (correct?)