diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 3e97f95..8abba5f 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -8371,6 +8371,7 @@
 	    if (ASCII_ISALPHA(*arg)
 # ifdef FEAT_CLIPBOARD
 		    || *arg == '*'
+		    || *arg == '+'
 # endif
 		    || *arg == '"')
 	    {
@@ -8381,6 +8382,7 @@
 			 (islower(redir_reg)
 # ifdef FEAT_CLIPBOARD
 			    || redir_reg == '*'
+			    || redir_reg == '+'
 # endif
 			    || redir_reg == '"'))
 		{