Per post #4 on this forum article (active as of ): Default e-mail client not chosen ? Solved - Windows 10 Forums the following registry edits need to be made: The 'Default Programs' section of the Settings App on Windows 10 does not appear to set the registry keys which MAPI uses to determine which mail client shall be used. Registry Modifications, Set 1: Specify Mail Client They have only been tested on the system described herein. Also, use these modifications at your own risk. For instructions on making a registry backup, a Google search will turn up plenty of results. As per the usual recommendation, make a backup of your registry before attemping modifications, particularly if you are not familiar or comfortable with working with the Windows registry. I suspect similar modifications would enable other third party MAPI-enabled mail clients to function as well.

I performed two sets of registry modifications using the built in Windows Registry Editor (regedit), after the second of which the problem was resolved and I was once again able to send invoices using Quicken 2017 Home & Business and Windows Live Mail 2012. I additionally attempted to install Mozilla Thunderbird to provide a current, supported (within its development community) email client, to no avail. Ultimately the representative gave up and claimed it was a known issue and the developers were working on it. I spent probably an hour on chat with Quicken support (since 2017 is still supported) trying to get clarification from a representative who suggested that Quicken only works with an Outlook account, but couldn't seem to grasp the difference between, nor get clarification on whether that meant they required an email account, or any email account configured in a desktop client version of Microsoft Office Outlook. Recent updates in Windows 10 and Quicken seemed to cause more and more trouble with the emailing capability. Previously I had been using the 2013 version with WLM, and the 20 versions of Quicken Home & Business with Outlook Express 6 on Windows XP x32. Prior to the upgrade, I had been happily using Windows Live Mail 2012 to email invoices to my customers with Quicken Home & Business 2017. I encountered the 'Mail system support is not available' problem personally after upgrading my Windows to a fresh install of Windows after installing a new SSD.

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Quicken home business 2017