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The username is considered a key in the system for many functions such as uploading learning records and attendance records. As of version 3.5, you can change the value of the username just like any other field, as long as "Allow renames" is set to "Yes'.
In other words, if you had to change the username for a user where username=jsmith and idnumber=12345, you could create the following CSV file. In the "User mapping" section you would map the idnumber from the CSV file to the idnumber field in the system, and set "Allow renames" to "Yes". This would change the username from jsmith to jdoe. (Note that while "idnumber" is suggested in here, you can use any unique identifier in the user's profile.)
username,idnumber
jdoe,12345
Tip: Moodle "out of the box" suggests to use a field called "oldusername" to rename users. This is because Moodle "out of the box" doesn't support user mapping. If you do have a CSV file with the "oldusername" column because you've migrated from Moodle "out of the box" to Dual Code's system, you can still rename users by ensuring you set the proper mapping and other fields in the user upload wizard properly as per the screenshot below.
Encoding File Format
On the initial "Upload user" screen, you may select the file encoding format from a pull down list. These include UTF-8 (the default), ASCII, ISO-8859-1 to ISO-8859-11 or any one of over 36 formats. You need to make sure that your CSV file matches the encoding format that you select here.
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