It is always nice to get hold of cool add on’s to applications you use often, especially if they add extra cool functionallity. This add on to outlook will help you reduce your mailbox size by deleting redundant data (which is always nice as your mailbox just keep growing), I won’t go into details as this blog post explains it nicely. Visit Grand Stream Dreams for the whole story including how to download and implement it. The installation of the plugin is done more or less like this (taken from Grand Stream Dreams); INSTALLING * Firstly, download the ZIP and save it locally. * Create a folder you’ll find again – I’d suggest C:\Program Files\Thread Compressor or similar. * Start a command prompt – WindowsKey-R then cmd <enter> (though if you’re on Vista or Win7, just press WIndowsKey, type cmd, then right-click on the cmd icon and choose “Run as Administrator”) In the command prompt, type: cd c:\program files\thread compressor (or wherever you put the files) regsvr32 comdlg32.ocx regsvr32 msflxgrd.ocx regsvr32 tabctl32.ocx regsvr32 threadc4.dll Download the latest CDO file from here, save it somewhere, expand it out and run the install from the ExchangeCDO.msi file. Now start Outlook: how you actually install the addin will vary depending on your version of Outlook, but try: Tools | Options | Advanced | Add-ins, or Tools | Trust Center | Add-ins | [then hit Go to manage COM add-ins] and add the threadc4dll file manually. If it’s successful, you should see Comrpess Threads on the Tools menu, and you’ll get a splash screen next time you start Outlook CAUTION! The default setting for this plugin will delete data in your mailbox (which is the whole point of the plugin), so be sure to understand how it works before implementing it 🙂