We have just set up a partnership with a vendor, this vendor sends emails to users within our environment to advise when accounts are created/modified etc. The emails have the logo of my company embedded in them.
When we receive these emails the image takes 17 to 30 seconds to download, if sent to external addresses the image loads instantly. This has been tested using the same browser and mail client for both email accounts, external account is instant, internal account is slow.
How can I speed this up for my users?