Before installing Window 7, I installed the original Windows XP Professional on the
machine, I found myself to be very smart doing this.
Unfortunatly now that Window 7 is installed on this machine the disk can not be
accessible. Disk Manager says Dynamic Disk Status "Invalid". What should
I do to gain control over this disk again? I can convert it to a basic
disk (only option available in disk manager) but then I will lose the
data that it contains. The screen shot is shown below:

Now I know mainly because I was using a WINDOWS 7 HOME EDITION which does not support dynamic disks, so an Invalid Dynamic Disk was shown in Disk Management. In fact, all the Home edition of Windows do not support dynamic disks such as XP Home, Vista/Win 7 Home Basic and Premium Edition.
There are three ways to solve this problem, the first one is to re-install an Operating System (eg. XP Professional, Windows 7, 8 Ultimate, etc) that supports dynamic disks to access the disk, the second one is to directly clear data and revert it to a basic disk, the third one is to convert it to a valid basic disk without losing data by using AOMEI Dynamic Disk Converter Professional Edition.
AOMEI Dynamic Disk Converter Professional Edition can convert an invalid dynamic disk to basic disk to fix it without losing data, even if the dynamic disk can not be accessed in Windows 7/8/Vista Home Basic Edition, and it's secure and easy!
Repair Invalid Dynamic Disk Steps:
1. Select an Invalid Dynamic Disk that you want to repair.
2. For data security, if any data will lose during the repairing process, you will be prompted by the program.
3. Confirm operation: make sure you wish to repair the selected invalid dynamic disk.
4. Executing...Report of the repair is complete,
5. After completing, you need restart the computer to take effect, and then the disk becomes valid!
The following is a screen shot of AOMEI Dynamic Disk Converter Professional Edition:

Note: Before using AOMEI Dynamic Disk Converter, please read FAQ in order to avoid making unnecessary mistake.
For more information: AOMEI Dynamic Disk Converter Professional Edition
Buy Now AOMEI Dynamic Disk Converter Professional Edition.
Tips: After repairing the invalid dynamic disk, you can manage your basic disk partition with AOMEI Partition Assistant:
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AOMEI Dynamic Disk Manager:
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