illegal character filter

Is there a Sharepoint add-in that would seamlessly filter out illegal
characters as a file is being uploaded into a Sharepoint Library....ie,
either change all illegals to one legal character, or just eliminate the
illegal characters....so users are not impeded by error dialogs???
Seems like this should be part of Sharepoint itself...

Alternatively, a simple watch folder on the desktop that does the same thing
for any files/folders/emails dropped into it....so they can then be dropped
into Sharepoint without any further fuss...

You would need to code an event reciever to do a special edit.

You would need to code an event reciever to do a special edit.
The included one is already checking the file name is legal, but
you are asking it to change the name to something legal based
on your logic.

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