Yahoo has prevented users of its Yahoo Mail services batch forwarding emails in a move to lock down the platform and make it effectively impossible for anyone to leave.
Mail Forwarding is a useful, but lesser known, feature that allows you to send on all mails to a particular address, thus allowing you to keep tabs on an old account in the (sometimes years) it takes for people to start using your new one.
The problem is that, while not everyone knows about this feature, hackers often do and having accessed your account are able to use the service to turn your email address into a spam-botnet participant.
Think of it as like someone redirecting your post to the wrong house so they can steal your pay cheques.
Nefarious use is a problem, but many people, for example those who may have started with a Yahoo account with a silly name and then realised it was stopping them getting a job, actually found the service useful.
At a cynical level, it could be seen as a ruse to get people visiting the Yahoo portal again. It could equally be a valid security measure reflecting Yahoo's poor record at keeping customers' mail safe.
But a side effect will be to stop a mass exodus after it was revealed last week that Yahoo had scanned incoming email to its servers on behalf of the US government, shortly after admitting that up to 500 million passwords were leaked in 2014 but that the company hadn’t thought to mention it.
In short, Yahoo is a mess and pulling out a key feature from its mail service could be the final straw for many in a long history of mistakes. After all, the out of office part still works. You turn that on asking people to note your new email address.
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