Removing Bitlocker and Un-Shrinking C Drive

Hi, I set up BitLocker out of curiousity and now I've removed it, but I still have a unused S drive taking up 1.46 GB.

What I want to do is go to Computer Management, then delete the S:, then expand C:, but if I try to delete the S: I get the message "Windows cannot delete the active system partition of this disc."

Note that I used the BitLocker Drive Preparation Tool to automatically do the partitioning for me. Also note that I have disabled BitLocker, and my drive is not encrypted at the moment.

Here's how Computer Management reports my drives:

C: Boot, Page File, Crash Dump, Primary Partition
S: System, Active, Primary Partition

I guess I need to make the C: the active, system partition, but I've no idea how, and I'm not 100% clear on the details of what the drive preperation tool did to my volumes so I don't want to take a wild stab at what to do.

I tried clicking C: and selecting make Active partition, but then I get the warning: "Only mark a partition as active if it contains a functioning operating system. If the partition lacks an operating system, marking it active might case your computer to stop working." Since the preperation tool was the one that fiddled with my volumes, not me, I don't know wether C: contains an OS, or whether it was moved (rather than copied) to S:, so I didn't want to risk trying that. Also, even if that worked, that would move the "Active" flag from S to C, but what about the "System" flag, what does that one mean?

Why didn't they make a Bitlocker Drive UN-preperation Tool to go along with the preperation tool?

Use at your own risk!

If you haven't already fixed this, here is what you do. Write it down and back up your data.

First you will need the vista installation disk so you will be able to repair your boot manager.
In the vista disk managment tool mark C: as active.
Restart your computer.
Boot up the vista install disk.
When the language selection screen comes up click next.
Click the repair link.
Select the c: partition.
Click next.
Click repair boot manager.
When it has finished restart your computer.
In the vista disk manager convert the 1.5 gb partition into unallocated space.
Extend C: so that it uses all the unallocated space.
Everything should be back to normal.

Use at your own risk!