How do I change header image in emails?

[Brainteaser]

Hi,
I am trying to change or remove the header in the greeting emails to new customers, order confirmation and other automatic emails that customers get from my store. Now these letters go with Zen- cart header.
I have tried to delete the header.jpg file from email folder and replace it with my logo. But oh mystery, even after I deleted the header it is still in the letters.
Please, help. What did I do wrong or what else should I do?
Thanks in advance

[DrByte]

Your email program is caching the image.
Clear your browser cache, and shut down your email program and restart it. Then your updated header.jpg will be re-cached when you open the email again.

[Brainteaser]

Thank you, DrByte.
Everything is workng right now. :)