Before you start
- An Android phone with a microSD slot
- A computer and card reader (recommended for recovery)
Method 1 Try the quick fixes first
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Step 1: Restart and reinsert
Turn off the phone, remove the card, check the tray and the card’s gold contacts for dust, reinsert it firmly and turn the phone back on.
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Step 2: Try another device
Put the card in a computer with a card reader. If the files open there, copy them to the computer straight away.
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Step 3: Repair on Windows
If Windows asks to scan and fix the card, let it. Or open File Explorer, right-click the card > Properties > Tools > Check.
Method 2 Recover files from a corrupted card
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Step 1: Use a recovery tool
On a computer, use a reputable free tool such as PhotoRec (open source), or Microsoft’s Windows File Recovery. They scan the card for photos and videos even if it shows as empty or unformatted.
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Step 2: Save to the computer
Always save recovered files to the computer’s drive, never back onto the card.
Method 3 Format the card on Android
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Step 1: Open storage settings
On Pixel/stock Android: Settings > Storage, then select the SD card. On Samsung: Settings > Battery and device care > Storage, tap ⋮ and choose the SD card (or Settings > Device care > Storage > Advanced on older models).
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Step 2: Choose Format
Tap ⋮ > Format (or Storage settings > Format). When the phone shows a notification that the card is damaged, tapping it also offers Format.
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Step 3: Pick portable storage
If asked, choose Portable storage so you can move the card to other devices. Internal storage encrypts it to this phone only.
Method 4 Format the card on a computer
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Step 1: Windows
In File Explorer, right-click the card > Format. Choose exFAT for cards of 64 GB and larger, or FAT32 for 32 GB and smaller, then click Start.
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Step 2: Mac
Open Disk Utility, select the card, click Erase and choose ExFAT with Master Boot Record.
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Step 3: If formatting fails
Use the free SD Memory Card Formatter from the SD Association, which follows the official SD standard.
When to replace the card
- The card becomes corrupted again within days or weeks.
- Formatting fails or the card shows as read-only.
- Its capacity looks wrong (common with fake “1 TB” cards sold cheaply online).
Buy cards from known brands (SanDisk, Samsung, Kingston, Lexar) from trusted sellers. For phones, an A1 or A2, U3/V30 card is a good choice.
Troubleshooting
The phone doesn’t detect the card at all
Test it in another phone or computer. If no device sees it, the card is dead; if others do, your phone’s slot or tray may be faulty.
“Card is write-protected”
Full-size SD adapters have a small lock switch; slide it up. microSD cards have no switch, so write-protection usually means the card has failed.
Frequently asked questions
Why do memory cards get corrupted?
Removing the card while the phone is writing to it, sudden power loss, fake or low-quality cards, and simple wear over time.
Can a formatted card be recovered?
Sometimes, with recovery software, if nothing new was written after formatting. Don’t count on it.
Should I use the SD card as internal storage?
Only if your phone is short on space and the card is fast and reliable. If the card fails, data on it is lost and can’t be read elsewhere.
Summary
Rescue your files on a computer first, then format the card from Settings > Storage > SD card > Format or with the SD Card Formatter. If it keeps failing, replace it with a quality card from a trusted brand.
