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You are your own worst enemy

you pay microsoft?

One guess: it is possible that your email client renders a link preview (either by default or on hover)

That causes a request to the link - which ”wastes” it’s one time usage

@jiraTicket never thought of that, but it sounds plausible. Maybe those links are only supposed to work in Outlook mail

@usr--2ndry Nah, it's unthinkable that the links are designed for a specific email client. A link is a link.

It's just that some programs will notice when a link is rendered and try to render the page title for that link - and that causes a request to be sent to the page.

Other email clients do this too.

And it's also done if you paste a link on facebook - they will make a request to that link to fetch it's image. If you write a link in google docs and hover over it - it'll render the page.

So essentially "one time usage only"-links can be screwed by many programs.

@jiraTicket So essentially, one-time-usage-only-links should not exist for so many reasons, but most importantly they violate the Principle of Idempotence that should apply to all GET actions on the web.