When the emergency method fails, it fails in one of five places — and each place has a short, ordered set of checks. Work the list by symptom instead of randomly retrying, and keep the honest fallbacks in view: sometimes the right fix is a different phone.
A failed attempt at 11 pm feels like the method is broken. It almost never is — it is one specific link in a five-link chain: the phone seeing the drive, the app reaching it, the write completing, the PC booting it, the image being sound. This page isolates each link with its signature symptom, so you fix the link that is actually broken instead of rewriting the USB three times on a phone that cannot see drives at all.
Symptom: you connect everything and nothing appears — no storage notification, no drive in the file manager. This is the OTG gate from the requirements page: the phone lacks USB host support, the adapter is charge-only, or a brand's OTG toggle is off (some phones switch OTG off automatically after idle minutes — find it in Settings and switch it on just before writing). Test with a USB mouse or a different drive: if the phone sees nothing through any adapter, this phone cannot do the job — no app fixes hardware. Go straight to the fallbacks below.
Symptom: the drive shows in the file manager but the writer app says no device, access denied, or shows an empty list. Android guards USB devices behind a permission prompt — if you dismissed it, the app is blind until you grant it: unplug, reconnect, and accept the prompt (ticking "use by default" saves repeats). Also give the app its storage permission, and check that no other app (a file manager that grabbed the drive first) is holding it — close the others and reopen the writer. On phones with a memory card, make sure you are selecting the OTG drive in the app, not the card.
Symptom: the progress bar freezes, the app closes, or it reports a write error at some percentage. Causes, in order: a loose adapter shifting mid-write (reseat everything, keep the phone flat and untouched), the battery saver killing the app (set the app's battery use to unrestricted and keep it on screen), the phone overheating and throttling (cool it down, case off), and a genuinely faulty pen drive (try a different drive — cheap drives die exactly like this). Every interrupted write leaves a corrupt drive: the only fix is a complete fresh write under better conditions, not a resume.
PC ignores the finished USB: work the boot page in this set — another port, the boot menu key, the UEFI entry, Secure Boot enrolment for Ventoy. One phone-specific extra: a small number of ISO images are known to dislike being booted through Ventoy while working fine written directly (and a few very old images want legacy boot) — if a Ventoy copy refuses on two PCs, write that same ISO directly and try again before blaming anything else. Installer starts, then errors or freezes: suspect the image itself — a download that silently broke. That is the checksum case from this set: verify the SHA-256, and re-download on a better connection if it differs.
Know when this phone has told you no. The fallbacks, in practical order: another Android phone in the house (OTG support varies by model, so a different phone genuinely changes the odds); any working PC at all — a neighbour's, a relative's, an office machine, a cyber café — where the same ISO can be written with the PC tools in two minutes of actual writing; and a ready-made bootable USB if anyone nearby keeps one. None of these is a defeat. The method on this page exists for the night when none of them is available — and if one of them is, using it is the professional choice, not a shortcut.
Compare your symptom with the video's smooth run — the difference between the two is almost always one of the five links on this page.
▶️ Watch Full VideoThe PC never tried the USB. It boots its internal drive by default; you must catch the one-time boot menu in the first seconds and choose the USB's UEFI entry. That is the boot case guide in this set — the USB itself is probably fine.
Yes, and it is a nasty one — a drive labelled 64 GB that really holds 8 GB accepts writes happily and loses everything past its true size, producing installers that fail at random points. Buy drives from reputable sellers, and be suspicious of any drive whose real, tested capacity you do not know.
If the phone fails the basic OTG test — no drive, no mouse, through a known-good adapter — stop immediately; that is hardware. Otherwise, two organised attempts with one change each will find any fixable cause. Beyond that, a fallback route is faster than a third retry.