Everything is ok but windows 10 says disk structure is corrupted

@papmodern
Before coming here, your 3TB disk has been manipulated in many ways that could have changed the original partition structure. If you initialise and format a GPT drive as an MBR drive, MBR can see only 2TB and rest of the space will remain unallocated and inaccessible.

It is possible that this could have triggered the unspecified error when you ran CheckDisk.. Can you post a screenshot of Windows Disk Management showing your 3TB drive in the present condition?

If you have already wiped it clean, initialised as GPT and formatted it, full 3TB should be accessible. Run CrystalDiskInfo as advised by Bree in his post #13. If it shows as good, the drive may still be good if my above presumption is right.

Post the results for Bree to examine it and give his opinion. He is more knowledgeable on this topic.

(When people bring in their problems with larger than 2TB drives, the very first question I ask is How old is your drive? Do you know whether your drive is an MBR drive or GPT drive?. Older drives can be MBR drives. Those employ a special Drive Translation Circuitry inside the enclosure that enablles MBR to see upto 16TB overcoming the 2TB limitation. The data recovery procedure is different than what will one do in case of a GPT drive. Newer larger than 2TB drives are GPT drives. If the drive is visible in Disk Management, I ask for a PW screenshot that will show whether the drive is an MBR or GPT drive)