u-pathname-filter

The server can be configured to disallow operations involving what it considers to
be illegal pathnames.  A pathname is considered illegal if it contains non-printing
characters, spaces, or begin with a period.  For anonymous users, this feature is
controlled by a-pathname-filter; for non-anonymous users, it is controlled by
u-pathname-filter.

Non-anonymous users often need to upload dot-files to their home directory (.cshrc, .profile, .signature, etc.), so you should avoid turning on u-pathname-filter.

Examples:

Recommendation:
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