Not implemented error message in Outlook 2013

Hello,

When I try to send an Email to my client suddenly an error message display: “Not Implemented Error Message in Outlook 2013”. There is issue in the functionality of MS Outlook, it creates big trouble for me. I’m getting frustrated from this error. I have to send 100+ emails to my client to inform about our updated company policies. I have searched over net and found so many solutions paid as well as non-paid. I’m non-technical person, I don’t know how to perform troubleshooting in outlook. But still I tried my best and perform these manual methods like,
1. Turn Off Antivirus Scanner
2. Deactivate All Outlook Add-ins
3. Reset Send or Receive Settings
4. Repair MS Office Installation
5. Create a New Profile of MS Outlook
6. Run Scanpst.exe Application

There are various manual solutions available on internet which I found from below references. But still facing same issues. I have also tried free repair tool provided by Microsoft to resolve all outlook errors.
https://support.microsoft.com/en-us/office/repair-an-office-application-7821d4b6-7c1d-4205-aa0e-a6b40c5bb88b?ui=en-us&rs=en-us&ad=us
https://answers.microsoft.com/en-us/windows/forum/windows_10-hello/error-message-microsoft-outlook-not-implemented/00919a46-925a-4239-9c2b-358519060500


Please help..