Files and Data loss when sd card is changed from java supported phone to android phone I have changed my micro sd card from Samsung Star2 S5263 which is running on Java OS to a new android phone. Later I have connected my android phone to my PC to copy some files from the system. 

And after copying, I have placed my sd card into my old phone (Samsung Star2 S5263) only to find some of the files, images and videos are missing. When I tried to open those, it says invalid file format.

Files which were absolutely fine a few minutes ago, now says invalid file format. When I have connected to the system, I haven't touched these files. Any reason why this happens? How to get the files back? (Those images are absolutely important!!)

Thanks
If you removed the micro SD card from a device (any device) while it was still in use, this can cause filesystem corruption. This can often be repaired by connecting it to a card reader on your PC and using a disk scanning tool (e.g. ScanDisk on Windows).