So if i got signed out on desktop, there would then be no way to log back in at all anymore? Or would i still be able to then install the app on a phone (even if it's not the one that has the number for the account?) and then log in using the number, then log in to my account on desktop after that even though i've not used the phone app before? Managed to get in via an alternate active session but that's obviously not an entirely reliable way as it seems the web version doesn't stay logged in for very long. I had assumed that the SMS message was just for some reason not being received by phone last time I logged in, didn't realize that's just not a thing anymore.

I only use telegram on desktop and haven't used it on phone at all as the phone it's linked to can't really use the app. What do you think about this 'security' feature? Tell us in comments!

In other words: you must have at least one active Telegram session to log into Telegram on PC or Web. The only thing you can do for now is to first create a new session using your mobile device, auth via SMS and then log into Telegram on PC/Web via 5-digit code in other session or QR Code. There has been no public statement on this yet, and we ( r/Telegram mods) don't know the reason behind this decision. Also it seems to be a strange 'security' feature, because it makes user's life harder with no possible spam protection. This makes impossible to log into Telegram if you don't have any other active sessions. Instead, the app sends auth code to all other active user's sessions. Since April 20, 2021, Telegram stopped sending SMS when user authorizes from desktop or web Telegram apps. So here's a quick public notice about it: We ( r/Telegram mods) are getting a significant number of messages in modmail with question: 'I cannot log into Telegram from PC/Web: SMS doesn't arrive'.

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