diff --git a/Gui/CustomerView.qml b/Gui/CustomerView.qml
index 6aec469..bb861d1 100644
--- a/Gui/CustomerView.qml
+++ b/Gui/CustomerView.qml
@@ -178,7 +178,7 @@ GridLayout
         Layout.columnSpan: 3
         validator: RegularExpressionValidator
         {
-            regularExpression: /([\+!#$%&‘\*\–\/\=?\^_`\.{|}\~0-9A-Za-z]{1,185})@([0-9A-Za-z\.]{1,64})\.([a-zA-z]{2,5})/
+            regularExpression: /([\+!#$%&‘\*\–\/\=?\^_`\.{|}\~\-\_0-9A-Za-z]{1,185})@([0-9A-Za-z\.\-\_]{1,64})\.([a-zA-z]{2,5})/
         }
     }