Can't open xml file after saving and closing the file

[ozzybayman]

I already make xml file and make some tab in there and when it tested it works fine but after saving and closing app when I open the file again it says

ERROR: Index and length must refer to a location within the string.
Parameter name: length

and I can't open the file unless I delete all of tab on view section

[harborsiem]

Please send XML File .

[ozzybayman]

RIBBONUI.zip