EOS Rebel T7 won't turn on properly with old SD card, OK with new SD card

[Jaysonwrd]

I have recently gotten a new sd card for my camera, i still have my old one that previously was working the day of that i got the new sd card the next day after using the new sd card i went to put the old one back in which is still fairly new my camera doesnt turn on right away, i have to turn it off take out the battery then plug it back in and itll "turn on" a rapid flashing led flashes then slows down but nothing pops up on my screen nothing works but the camera is on just the only thing that works is the built in flash. the built in flash will go up when i click the button but the screen doesnt turn on nor does it take pictures, but when i put the new sd card in the camera it acts perfectly fine.... does anyone know what can be the problem? 

[stevet1]

Jaysonwa4d,

It so7nds l8ke your card may have gotten corrupted somehow. It probably would be best if you could reformat your old card in the camera.

If you can't re-format it, you should probably throw it out.

Steve  Thomas

[Jaysonwrd]

i have a 128GB card never had a problem with it and i did reformat it again which it was completely fine and i put some new photos on the card that i lost and now it doesnt even want to turn on like the only thing that works is i can press the button to open up the built in flash other than that it wont take pictures and i have a black screen but what makes it werid is that the sd card works perfectly fine when i plug it in to my computer.

[Waddizzle]

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@Jaysonwrd wrote:

1. i have a 128GB card never had a problem with it and i did reformat it again which it was completely fine and i put some new photos on the card that i lost and now it doesnt even want to turn on like the only thing that works is i can press the button to open up the built in flash other than that it wont take pictures and i have a black screen but what makes it werid is that the sd card works perfectly fine when i plug it in to my computer.

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Uh-oh.  I just noticed a red flag.What do you mean by putting some photos on the card?  Also, are you using the SD cards as long term storage to store your photos?

You should not allow other devices to write to your memory card.  Data corruption on the card is almost a guarantee.  I would set the card aside and never use it again.  You might be able to recover the card by doing a low level format using a Windows based computer.  But the data is most likely lost.

Data corruption is also a risk when using SD cards for long term storage.  A computer hard drive is much more reliable than any type of removable storage media.

[Jaysonwrd]

ohhhh no im not using it as a long term storage a couple of days ago i was dowloading pictures to my computer so i can put specific ones on a google drive of some photos i took for my friends and it randomly formated automatically no warning nothing just said it was formatting to the computer so i lost every picture on the sd card. i then went on disk drill and got them back but before that i reformatted the card to the camera and it was working perfectly fine but when i put all the photos back on the sd card so i can still use that sd card on my camera for taking pictures my camera doesnt "turn on" like its on because the built in flash pops up but the screen doesnt come on no sign of being able to take a picture when you press the button to take one its just blank but when i put my brand new sd card in, it acts completly fine.

[Waddizzle]

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@Jaysonwrd wrote:

ohhhh no im not using it as a long term storage a couple of days ago i was dowloading pictures to my computer so i can put specific ones on a google drive of some photos i took for my friends and it randomly formated automatically no warning nothing just said it was formatting to the computer so i lost every picture on the sd card. i then went on disk drill and got them back but before that i reformatted the card to the camera and it was working perfectly fine but when i put all the photos back on the sd card so i can still use that sd card on my camera for taking pictures my camera doesnt "turn on" like its on because the built in flash pops up but the screen doesnt come on no sign of being able to take a picture when you press the button to take one its just blank but when i put my brand new sd card in, it acts completly fine.

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Do not attempt to write any data to the SD card and then put it back into the camera.  I strongly suggest that you set this SD cards aside and never again put into your camera.

I recommend that you purchase a new Levar or SanDisk SDHC card, 32 GB or smaller.  Only use the full size cards.  Never use the micro-SD cards that require an adapter.  Only purchase your memory cards from a Canon Factory Authorized Dealer.  

I use B&H for memory cards.  Avoid the online marketplaces like Amazon and Best Biuy.

[Jaysonwrd]

Thats what i have... i have a 128GB sandisk SDHC card i dont have a micro sd card and i dont need an adapter it just a dongle thingy so i can hook it up to my laptop since i dont have sd card slot to insert in the laptop but i have an dongle type thing where i plug into my laptop and can put the sd card in the slot

[Waddizzle]

The Rebel T7 is a part of the EOS xxxxD family of entry level cameras, which seem to be a bit finicky when it comes to memory cards.  

For best results you should follow the above advice to format your memory card in the camera, with “low level” option enabled, prior to first use. This is a best practice for any camera that uses SD cards.  

I would add the caveats that pertain to your family of cameras. Stick to only using SDHC cards, 32GB or less.  For whatever reason, these models will frequently report card errors with SDXC cards, 64GB and larger.  

Finally, never use the micro-SD cards that need a plastic adapter. They are not included in the card types recommended by Canon. 

[Tintype_18]

Good advice from the community. I have a T7 and have never had a problem with the card. I only use name brand cards of up to 32GB.

[normadel]

It is crazy to even want to use a 128 GB. SD card. It is never good practice to fill a card up, and a 128 will hold many thousands of images. The SD card should NOT be a storehouse. You risk losing everything should a problem arise with the card or camera. Move files to a computer, external storage etc. frequently to keep them.  Use smaller cards, move files off them, and format the card before shooting again. Have more than one memory card.