Overview

If it seems like the Postwire plugin has disappeared and you are having difficulties re-installing it, check to see if the plugin is disabled.

This article will show you how to check and re-enable the plugin.

Process

You will need to extrapolate these instructions for the particular version of Outlook you are using, but the basic steps for checking the plugin in the Trust Center are similar across all versions. For Outlook 2007: 

1. From the menu bar, select Tools > Trust Center.
2. Click on the Add-Ins tab. 
3. Check if the Postwire plugin is in the Inactive or Disabled list (it is probably in the Disabled list). 
4. If the Postwire plugin is in the Disabled list, select Disabled Item from the drop-down (at the bottom of the dialogue box). 
5. Click on the Go… button. 
6. A dialogue box pops up. Select the Postwire plugin from the list and click on the Enable button.

That should do it if the plugin is disabled. You may need to restart Outlook. However, if you are still having difficulties, try uninstalling and re-installing the plugin.