Firstly, let’s use the card reader read a few more SD cards to confirm whether it is a problem with the card reader or the problem with the SD card, and then find a solution. If it is a problem with the SD card, you can try the following methods:
If the SD card can view the photos normally in the camera but cannot be recognized in computer, it is likely that the driver of the SD port does not match. To get the correct SD card driver update, if there is a yellow warning icon in the device manager after update, and there may be incompatible due to u disk protection software installed in the computer, the SD card can be read by restarting the computer.
Check the SD card carefully.
2.SD card touches virus.
If the SD card gets virus, it will not be able to read properly. If there is virus in the SD card, then running on anti-virus software to scan the SD Card when you connect it to the computer by card reader.
3. The card slot is squeezed or even deformed.
Nowadays, there are more and more ultra-thin cameras in the market, and the design of the card slot is becoming more and more unconventional. If one non-original battery is used, the card slot can be squeezed because the thickness exceeds the specification, and the SD card of the camera cannot be read. If it is for this reason that the card reader cannot read the SD card, then the original battery needs to be replaced.
4. The card slot wire is rusted or bent.
Most SD cards support plug and play, however, the frequent insertion of SD card will cause the card slot wire to bend or rust excessively. When the card slot wire is rusted or bent, just use one needle to pull the wire down; if it is rust, you can clean it.
May be card reader gets virus. If the card reader has virus inside, the picture and file will be hidden, so you can't see it in computer. It can be resolved if you adjust the folder option. Another possibility is that the virus has damaged the file and it cannot be used normally in computer. The solution for this problem is to open “my computer”, left click on the tool, select "Folder Options", click the left button, select the View tab, and there is an advanced setting with a " Hide protected operating system files", you must cancel this option. This will allow you to see hidden files. If the computer system is WIN10 version, the operation step is to open the computer - left click on the tool, select "folder options", click the left button, select "show all folders" in the navigation window, you can see Hidden files.
Of course, there is another situation. You can't read the image directly in computer with the card reader, but you can only see it when you play it back in the camera.
This is generally because your card reader version is too old. If your SD card is SDHC high-speed card, many old-style card readers are not reading. It is recommended to try a new card reader. The card reader is not broken; you can connect to another computer. You try to see if your XP system comes with the correct driver.
If it is not the problem of the card reader itself, then it is definitely the problem of the SD card. For the problem of SD card, you need to use the memory card repair tool to proceed the formatting. This way will recover SD Card by chance, but the data inside will be cleared, so it is recommended to restore the data before repairing.
The card reader cannot recognize the SD card, it involves in two parts, one is the SD card and the other one is the card reader, so we need to use the exclusion method to determine whether the SD card or the card reader is faulty, then problem will be easily found. If it is the problem of the card reader, we can use a few more readers to test, and we also cannot rule out the problem of the USB port in computer, so we need to find more computers to do the test, and finally we can find the key to the problem and solve it one by one.