I just found out that the upload from excel (xls) to a collection doesn't work with 5.1 any more. We upgraded an existing 5.0 to 5.1 and this is now bugging us. The setting is normally done in the ords by adding the four lines to support uploading excel:
However in APEX 5.1 the simple page with a button to start the upload and the file browse item produces an error.
I tested this on multiple environments where there was an upgrade from 5.0 to 5.1 and it is the same thing.
Anyone with an idea ?