2FA while traveling abroad: what breaks, and when
SMS codes stop at the border, and switching to an app has to clear the SMS check first. A dated plan before you fly, plus what to try once you are abroad.
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Posts on two-factor authentication: which second factor to use, where backup codes belong, how to leave Authy, and what zero-knowledge really costs.
Locked out of email and 2FA: breaking the loop
Your second factor lives in an app whose recovery runs through an email that needs that same app. How to map the chain, find the ring, and break it.
Authy code not working: three different failures
Authy fails in ways other authenticators do not: a retired desktop app, multi-device, a backup password nobody can reset, and no export to fall back on.
Microsoft Authenticator code not working: what to do
Push approval and six-digit codes fail for different reasons. Number matching, work and school accounts, and what a cloud backup restore actually brings back.
Google Authenticator code not working: fixes in order
Why Google Authenticator codes get refused: the clock setting Google moved out of the app, codes rejected after a new phone, and the QR settings it ignores.
Is it safe to screenshot your 2FA QR code?
What that QR code actually holds, what a photo library does with it once it syncs, and the triage for screenshots already in your camera roll.
I deleted my authenticator app: what comes back
Reinstalling restores only what something was already holding. What each app brings back, why your 2FA is still on, and the order that gets you in tonight.
How to use an authenticator app on two devices
The same six digits on a second phone or laptop: why it works, the three routes to get there, and the button that quietly kills every device you set up.
Can 2FA be bypassed? The five routes, ranked
Yes, but not by breaking the code. The five real bypass routes ranked by how often they reach an individual, and what to check on your own accounts tonight.
2FA code not working: causes and fixes, in order
Google Authenticator, Microsoft Authenticator or Authy code refused? Fix the clock in the operating system first, then the six causes that survive it.
Where to store your 2FA backup codes
A sheet of one-time codes is a bypass for your second factor. Where to keep it, what to do when you spend one, how to regenerate a set, and the yearly audit.
Authenticator app vs security key: do you need one?
What a security key does that an authenticator app cannot, what it costs, what breaks when you lose it, and the setup that uses both well.
Should your 2FA codes live in your password manager?
Bitwarden, 1Password, Proton Pass and Apple Passwords can all hold TOTP codes. What that protects, what it gives up, and who should keep them apart.
Authenticator app vs SMS: what SIM swapping changes
Why texted 2FA codes are weaker than an authenticator app: SIM swaps, port-outs, SS7, and the phishing both share. Plus how to move accounts off SMS.
Passkeys vs authenticator apps: do you still need one?
Passkeys stop phishing in a way 2FA codes cannot. How they work, why most accounts still need TOTP, and why account recovery so often falls back to codes.
An authenticator app with folders and groups
Most authenticators give you one flat list and a search box. Here is what folders, groups and separate vaults look like at a few hundred codes.
An Authy desktop alternative: 2FA in your browser
Twilio retired the Authy desktop apps in March 2024. If you want codes on the computer you work on, here are the options that still exist.
How to export Authy codes in 2026 (and why you can't)
Authy has no export. Here is what that really means, the methods people still suggest, and the safe way to move every token to a new app.
What zero-knowledge actually means, and what it costs you
Zero-knowledge is the reason we cannot read your codes. It is also the reason we cannot get them back for you. Here is the mechanism, and the trade it makes.
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