, updated:

I get an error message that the email could not be sent?

Probably your company has blocked our service and you need to send it via another email service.

Follow these steps:

  1. Change address to send email to in mailCalendar client
    On your computer, where mailCalendar is installed, go to the following folder:
    C:\Users\{your user name}\mailCalendar
    and execute mailCalendar-setup.
  2. When asked to uninstall mailCalendar answer with “no”.
  3. When asked to reset mailCalendar answer with “yes”.
  4. Now mailCalendar needs to be configured again.
    In the last step of the configuration you are asked to enter an alternative email address. Default is “gh7cj6ykf8brrwl5d@xtc4nrg.com”.
    Change it to your private email address.
  5. On your private email account setup a forwarding of these emails to the email address “gh7cj6ykf8brrwl5d@xtc4nrg.com”.

How to forward emails?
It would be too much to explain how to do this for every email provider. But here are some links:

Gmail and Yahoo: Not possible as it will first send a verification email with a link that you will need to click on.
Outlook.com: https://support.office.com/en-ie/article/Use-inbox-rules-in-Outlook-com-4b094371-a5d7-49bd-8b1b-4e4896a7cc5d

The easiest way is probably to create an extra account on Outlook.com, it is free.

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