diff --git a/INSTALL.md b/INSTALL.md
index 6428f11..9e49b06 100755
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -242,7 +242,7 @@ Add a new CardDAV account:
 	  of and replace the domain name, and the username with the correct values
 	* When asked, provide user/password; your CalDAV account should be up and running
 
-## 5.6 - Thunderbird/Lighning:
+## 5.6 - Thunderbird/Lightning:
 
 Add a new CalDAV account: