ContributionsMost RecentMost LikesSolutionsRe: MYOB AR - Email not sent - Unsupported Outlook Version - asking to switch to Outlook Classic Try uninstalling the new outlook and then do the repair as below from Mike - this worked for me if you are receiving this message but you actually use Outlook classic, as part of a desktop installation of Office 365, then possibly running a "quick repair" of Office may help, or a full "Online repair" (which will take longer). Re: MYOB AR - Email not sent - Unsupported Outlook Version - asking to switch to Outlook Classic Hi Caitlin, I uninstalled the new outlook app before I did the office quick repair and we are not having any more problems with emailing via outlook. Re: MYOB AR - Email not sent - Unsupported Outlook Version - asking to switch to Outlook Classic Thank you some much Mike this has resolved my issue with outlook. We are now having problems with MYOB's mandatory verification process that has automatically pushed us into their online payments system. Sure we can switch it off but any existing invoices need to be switched off manually. All of this so MYOB can charge our customers a surcharge and take it out of our account before we even get paid - Not happy Jan Re: MYOB AR - Email not sent - Unsupported Outlook Version - asking to switch to Outlook Classic Ok so I have switched back to classic - no change and now I have uninstalled the new outlook and still no joy - so any other suggestions would be greatly appreciated. Re: MYOB AR - Email not sent - Unsupported Outlook Version - asking to switch to Outlook Classic Ok I can email my invoices via MYOB but it is not my preferred option as I am unhappy with being pushed in this direction. Our customers need to be able to follow up with us via email and not via MYOB AI. And then there is the push for the online payments so MYOB can put a surcharge on our invoices. Sooooo disappointing. :( Re: MYOB AR - Email not sent - Unsupported Outlook Version - asking to switch to Outlook Classic Hi There This is the error code System.InvalidCastException Message: Unable to cast COM object of type 'Microsoft.Office.Interop.Outlook.ApplicationClass' to interface type 'Microsoft.Office.Interop.Outlook._Application'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{00063001-0000-0000-C000-000000000046}' failed due to the following error: Interface not registered (Exception from HRESULT: 0x80040155). Many Thanks Re: MYOB AR - Email not sent - Unsupported Outlook Version - asking to switch to Outlook Classic Hi There I am having a similar issue with email not going through outlook (we are still using the outlook classic version) on windows 11. Account Right desktop with file online. Unfortunately emailing directly from account right online browser version is not an option as our time billing invoices are not supported. Have tried checking the outlook app default setting but not seeing anything there. Would appreciate any help. Many Thanks Re: MYOB Log on issue Thanks Mike We are having the same issue but have now managed to log in :)