Can anybody recommend a service that would let me check whether an email (sent via my or the service provider server) was picked up?
They discuss this functionality in their system but I'm looking for someone I can outsource it to.
It's not worth outsourcing. We just add a tiny gif that has a unique hash. When that file is requested record the hash and mark the identified message as read.
Seems like most e-mail clients these days don't load remote images automatically - do you find that significantly affects this technique?
The hashed image is the same method the big boys would use to record open rate.
Ok, but surely they have the same problem then?
Thanks - is there a library I can use? Wouldn't want to reinvent the wheel
I'll talk with Noah about open sourcing it. Right now it would take a little bit of effort, but it's probably worth it for the good of the community.
Do not rely on it. As the other message says it is trivial to do, but it will underrecord by a lot. Measure by actions not opens.