last friday (18.12.2009) we sent a newsletter to a mailinglist with a couple of addresses @t-online.de (biggest telecom provider of germany).
by chance we found out, that all subscribers with an @t-online.de address, cklicked on all links including the unsubscriber link, at exactly the same time. (certainly impossible) it seams, as an automatic filter/software clicked the links.
we've send couple of newsletters to the same mailinglist with @t-online.de addresses and never had problems.
i called t-online.de... but they seam not to know any changes they would have done.
i sent them the ip's to whitelist and hope, they'll care about it:
do you guys at cm also care about whitelisting of "non-english"/international supplier such as t-online, which is the biggest telecommunication provider of germany? or swisscom / bluewin for switzerland? or france telecom?
thanks for your support.
If they all clicked all the links, that suggests there could be some kind of automated software clicking all of them, perhaps an anti-fraud system. If you can contact support with more details we can take a look for you.
Regarding whitelisting, that is actually rarely used these days, most of the big providers don't offer whitelisting services. Instead, they use sender reputations systems and monitoring, which we are completely involved with.
Where major whitelists are still available we do get approved for them though.