diff --git a/reference/exec/functions/proc-open.xml b/reference/exec/functions/proc-open.xml
index e0930fbed3..ae03b9af8a 100644
--- a/reference/exec/functions/proc-open.xml
+++ b/reference/exec/functions/proc-open.xml
@@ -69,6 +69,13 @@
        In this case the process will be opened directly (without going through a shell)
        and PHP will take care of any necessary argument escaping.
       </para>
+      <note>
+       <para>
+        On Windows, the argument escaping of the &array; elements assumes that the
+        command line parsing of the executed command is compatible with the parsing
+        of command line arguments done by the VC runtime.
+       </para>
+      </note>
      </listitem>
     </varlistentry>
     <varlistentry>