Sometimes you may want to temporarily disable an Outlook 2013 add-in without removing it completely.  Here are the instructions:

Step 1. Go to Outlook Options

Click on File

Click on Options

Step 2. Go to Manage COM Add-Ins

Click on Add-Ins

Click on Go next to Manage: COM Add-Ins (shown below)

Step 3. Temporary Disable the Required Add-In

To do this remove the checkbox next to the item you want to temporarily disable and click on Ok

Most Add-Ins will be unloaded immediately but it is always a good idea to restart Outlook 2013 just to be sure.