[SOLVED] HDD not allowing me to use the full capacity?

[VikingIwan]

I have a 2011 iMac, which was recently in a repair shop because my HDD was failing, and I didn't trust myself to remove the screen to change the drive. The drive they replaced the old one with is a larger, 2TB drive. This was great, however there is a problem. It appears I'm only able to use 1TB of it. In disk utility, the Mac HDD partition has 1TB, even though the drive lists a capacity of 2TB. When I go to repartition it, it won't allow me to change the size of the partition to anything above 1TB. Can anyone help me and maybe explain why this is, and how to fix it?

Here are some screenshots that may be helpful:

 

[McHenryB]

Does it let you create a second 1TB partition?

 

[VikingIwan]

Does it let you create a second 1TB partition?

Nope, Only allows me to make another partition within the 1TB.

 

[McHenryB]

That's odd. I wonder if the shop imaged the disk and this is somehow confusing it into thinking that it is the same size as the old one. I'd be inclined to take it back to them and ask them if they can sort it out for you.