I'm reinitializing a HD, do I need a full format again?

[tat2jr]

I initialized a 4TB hard drive and then did did a full format as it was a new drive and I wanted any bad sectors to be marked. I need to change it from a MBR to GPT. Is there a way to do it without losing data (I'm sure there isn't), so my second question is, do I have to do the 48 hour full format again or will it save all the sector data that it found the first time? Thanks in advance.

 

[Phillip Corcoran]

You've got to delete all existing partitions in order to make it a GPT disk, so definitely no way to do it without losing data.

Full format.

 

[SuperSoph_WD]

Hey there, tat2jr!

@Phillip is right, you can't re-initialize a drive and change the partition table without fully reformatting it. If you want to make sure that you don't have any bad sectors, I'd advise you to use your HDD manufacturer diagnostic tool to test the drive's health and SMART data status.
Some manufacturer's also offer free formatting tools that will help you write zeros (fully erase) your drive. Writing zeros to all the sectors will mark the bad ones and get the drive back to its default condition.
It's highly recommended to do the full format, yes, so be patient with it. It takes a lot of time to erase it, due to the fact that your HDD's capacity is 4 TB.

Good luck!
SuperSoph_WD