problem with email

[johnmcburnie]

I tried to send an email on a mailing list but a message popped yup telling me that one of the addresses is no longer valid. However, it didn't tell me which one, and the message couldn't be sent. How can I resolve this please?

[licquorice · Accepted solution]

Binary chopping.

Keep halving the list until you find the culprit.

If there's 50 in the list, send to 25. If it sends the rogue is in the 25 you didn't send, if it doesn't its in that 25. Send to 12 etc etc etc

[johnmcburnie]

Thank you. I will try that

[licquorice]

I presume you weren't trying to send more than 49, as that is the limit you can send at once.