diff --git a/src/components/views/dialogs/CreateGroupDialog.js b/src/components/views/dialogs/CreateGroupDialog.js
index bda298ef0b..f38d92b482 100644
--- a/src/components/views/dialogs/CreateGroupDialog.js
+++ b/src/components/views/dialogs/CreateGroupDialog.js
@@ -55,8 +55,8 @@ export default React.createClass({
 
     _checkGroupId: function(e) {
         let error = null;
-        if (!/^[a-zA-Z0-9]*$/.test(this.state.groupId)) {
-            error = _t("Community IDs may only contain alphanumeric characters");
+        if (!/^[a-z0-9=_-\.\/]*$/.test(this.state.groupId)) {
+            error = _t("Community IDs may only contain characters a-z, 0-9, or '=_-./'");
         }
         this.setState({
             groupIdError: error,