In an early 2020 Windows update Microsoft have made a slight change to the behaviour of the mailto: command, which has resulted in problems with emailing direct from Medilink.
We are producing a fix in the 2020 R1 version of Medilink.
In the short term you will need to manually remove the &subject= section from the recipient field.
To provide a little more detail:
To send emails Medilink has historically added additional elements to the end of the mailto command. For instance:
mailto:person@email.com?cc=another@mail.co&subject=Call%20Me
...would create an email with the recipient as person@email.com, cced to another@mail.com and subject "Call Me".
However, due to a minor oversight, clicking to email a patient or referrer direct would look like this:
person@email.com&subject=
...and technically the ampersand should be a question mark in this case.
Previous to this latest Microsoft update, Windows would handle this as intended anyway, i.e. it would recognise that the ampersand was a delimiter even though it's technically incorrect. But now it doesn't.