Hi,
I tried to upload with these combinations:
Username (lowercase) + Email (UPPERCASE) = Uploaded
Username (UPPERCASE) + Email (UPPERCASE) = Not Uploaded
Username (lowercase) + Email (lowercase) = Uploaded
Username (lowercase) + Email (tOgGLEcase) = Uploaded
Username (tOgGLEcase) + Email (tOgGLEcase) = Not Uploaded
Username (UPPERCASE) + Email (tOgGLEcase) = Not Uploaded
Means it is not taking USERNAME in UPPERCASE.
We have ursename in this format A12345678 and to maintain uniformity in our all websites LMS, Registration etc we need to insert in UPPERCASE.

Debugging shows:
Debug info:
Error code: usernamelowercase
Stack trace:
line 46 of /user/lib.php: moodle_exception thrown
line 806 of /admin/tool/uploaduser/index.php: call to user_create_user()

and at the bottom of the page:
0.602139 secsRAM: 48.6MBRAM peak: 48.8MBIncluded 643 filesContexts for which filters were loaded: 1Filters created: 3Pieces of content filtered: 10Strings filtered: 0get_string calls: 1763DB reads/writes: 47/1DB queries time: 0.01436 secsticks: 60 user: 54 sys: 5 cuser: 0 csys: 0Load average: 0.37Session (core\session\database): 72.3KBCaches used (hits/misses/sets)core/databasemeta** static acceleration *: 22 / 14 / 0cachestore_file: 14 / 0 / 0core/string* static acceleration *: 3082 / 406 / 0cachestore_file: 406 / 0 / 0core/yuimodulescachestore_file: 3 / 0 / 0core/htmlpurifiercachestore_file: 1 / 1 / 1core/langmenu* static acceleration **: 5 / 1 / 0cachestore_file: 1 / 0 / 0core/plugin_managercachestore_file: 3 / 0 / 0core/coursemodinfocachestore_file: 1 / 0 / 0core/repositoriescachestore_static: 0 / 10 / 20Total: 3538 / 432 / 21
This page is: General type: admin. Context System (context id 1). Page type admin-tool-uploaduser-index.
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