A recent MS Office 2016/365 patch broke the Act!/Outlook integration, preventing email history from being created and causing Act! to crash when trying to email from Act! For more information please see the statement from Swiftpage below.
Swiftpage have released updates for Act! versions 18 & 19 as below. Click here to see the Knowledgebase article.
Please visit the Act! Download Center to access the update for your version.
NB: Update 3 for Act! 19.2 was released on 27 July and includes an additional critical Outlook fix where email histories are not attached. The update also includes fixes for the RTF control and AEM. See the list of fixes below:
3rd Party Add-ons
There are a couple of really good 3rd party add-ons that have more functionality than the standard Act! Outlook Add-ins, plus they purportedly don't have the same problems with Outlook 2016/365. See Act4Outlook