Hi johnathan,
If Vista is the System partition , and you are currently booting into it, you may find this does the trick:
Open an elevated command prompt and type: ( press enter after each command)
bcdedit /copy {current} /d "Windows 7"
It will return a long number, a GUID, in brackets. Use that , including the brackets, in the following commands:
bcdedit /set {THE-GUID-YOU-GOT} device partition=D:
bcdedit /set {THE-GUID-YOU-GOT} osdevice partition=D:
Close cmd prompt.
If you have any more questions, please post a screenshot of the Disk Management window, and also of bcdedit command window ( just type bcdedit into an elevated cmd prompt , press enter - and the entries will be displayed).
You should see the Vista and the...