Not required to delete previous registration key after upgrade.

mountainduck/installation/index.md

@@ -111,14 +111,6 @@ You can install the registration key either in:
 This error message appears if you try to use an old license key for a newer version.
 [Upgrade](https://mountainduck.io/buy/upgrade/) your license to the latest version of Mountain Duck or download an older version from [Mountain Duck changelog](https://mountainduck.io/changelog/).
 
-#### Upgrade Issues
-
-After upgrading a license, a new license file will be generated.
-
-1. Delete the current license file from the application support folder.
-2. Download the new license file from the email attachment.
-3. Apply the new license file using double-click or copy the file into the application support folder.
-
 ### Windows Installation
 
 #### Error Code 0x24C