diff --git a/copyparty/__main__.py b/copyparty/__main__.py
index a48921bd..892c66c7 100755
--- a/copyparty/__main__.py
+++ b/copyparty/__main__.py
@@ -514,8 +514,12 @@ def get_sects():
                 """
             volflags are appended to volume definitions, for example,
             to create a write-only volume with the \033[33mnodupe\033[0m and \033[32mnosub\033[0m flags:
-              \033[35m-v /mnt/inc:/inc:w\033[33m:c,nodupe\033[32m:c,nosub"""
-            )
+              \033[35m-v /mnt/inc:/inc:w\033[33m:c,nodupe\033[32m:c,nosub\033[0m
+
+            if global config defines a volflag for all volumes,
+            you can unset it for a specific volume with -flag
+            """
+            ).rstrip()
             + build_flags_desc(),
         ],
         [
diff --git a/copyparty/authsrv.py b/copyparty/authsrv.py
index 84d3713e..c76718cc 100644
--- a/copyparty/authsrv.py
+++ b/copyparty/authsrv.py
@@ -859,7 +859,7 @@ class AuthSrv(object):
                     zd = split_cfg_ln(ln)
                     fstr = ""
                     for sk, sv in zd.items():
-                        bad = re.sub(r"[a-z0-9_]", "", sk)
+                        bad = re.sub(r"[a-z0-9_-]", "", sk).lstrip("-")
                         if bad:
                             err = "bad characters [{}] in volflag name [{}]; "
                             err = err.format(bad, sk)
@@ -935,7 +935,14 @@ class AuthSrv(object):
         value: Union[str, bool, list[str]],
         is_list: bool,
     ) -> None:
-        desc = flagdescs.get(name, "?").replace("\n", " ")
+        desc = flagdescs.get(name.lstrip("-"), "?").replace("\n", " ")
+
+        if re.match("^-[^-]+$", name):
+            t = "└─unset volflag [{}]  ({})"
+            self._e(t.format(name[1:], desc))
+            flags[name] = True
+            return
+
         if name not in "mtp xbu xau xiu xbr xar xbd xad xm".split():
             if value is True:
                 t = "└─add volflag [{}] = {}  ({})"
@@ -1441,6 +1448,12 @@ class AuthSrv(object):
             self.log(t, 1)
             errors = True
 
+        for vol in vfs.all_vols.values():
+            for k in list(vol.flags.keys()):
+                if re.match("^-[^-]+$", k):
+                    vol.flags.pop(k[1:], None)
+                    vol.flags.pop(k)
+
         if errors:
             sys.exit(1)
 
diff --git a/docs/protocol-reference.sh b/docs/protocol-reference.sh
new file mode 100644
index 00000000..38b22716
--- /dev/null
+++ b/docs/protocol-reference.sh
@@ -0,0 +1,2 @@
+vsftpd a.conf -olisten=YES -olisten_port=3921 -orun_as_launching_user=YES -obackground=NO -olog_ftp_protocol=YES
+