Print for Trial is an add-in for the Windows desktop version of Outlook. It will not work with either the Mac version of Outlook or the web page version of Outlook.
If Print for Trial has installed correctly the Print for Trial (PfT) button should be visible at the right hand end on the Outlook ribbon’s Home tab.
If it is not there then it is possible that Outlook disabled PfT if it took too long to load. To check this click File on Outlook’s ribbon bar. On the File page that appears select Options that appears on the left. This opens a new window with a menu list on the left. Select Add-ins. There is a list of installed add-ins – you may have to scroll down if it does not all fit in the space. The list has three sections: Active Application Add-inns, Inactive Applications and Disabled Application add-ins. (On older versions of Outlook you will find the Add-ins section on the Trust Center page.) If PfT is on the disabled list then look at the bottom of the window, below the list of add-ins. There is a drop-down labelled Manage COM Add-ins. Using the drop-down you can change this to Manage Disabled Items then click the Go button next to it. If PfT is on the disabled list select it. The Enabled button will then appear and you can enable PfT.
There is a Microsoft page about this here.
If that does not solve the problem then please send us the files that document PfT‘s installation & start up. You will find them your My Documents folder where there will be an Add-in Express folder. Send them to support at greenhillsoftware.co.uk.