diff --git a/doc/tor.md b/doc/tor.md
index 8c3cbb24fd..17cb85ace8 100644
--- a/doc/tor.md
+++ b/doc/tor.md
@@ -139,7 +139,10 @@ preconfigured and the creation of a hidden service is automatic. If permission p
 are seen with `-debug=tor` they can be resolved by adding both the user running Tor and
 the user running dashd to the same group and setting permissions appropriately. On
 Debian-based systems the user running dashd can be added to the debian-tor group,
-which has the appropriate permissions.
+which has the appropriate permissions. Before starting dashd you will need to re-login
+to allow debian-tor group to be applied. Otherwise you will see the following notice: "tor:
+Authentication cookie /run/tor/control.authcookie could not be opened (check permissions)"
+on debug.log.
 
 An alternative authentication method is the use
 of the `-torpassword=password` option. The `password` is the clear text form that