Xubuntu 10.04 install - can't detect other OS in dual boot

I had windows 7 installed with another operating system and Xubuntu a while ago in a triple boot. I recently made some major changes using EASEUS partition Master and also EASEUS Todo Backup. I made a sector by sector backup of the windows 7 and saved it to an external USB drive. I wiped my laptop main drive clean. Then I restored the sector by sector Windows 7 Professional alone back on my drive and removed the other two OS's from the triple boot. I expanded the partition to possess the entire laptop drive. Later I shrunk that partition as I wanted to add Xubuntu 10.04 again as I had done before all these changes. This time, when I ran the Xubuntu installer, and I got to the screen "Prepare disk space" it stated "This computer has no operating systems on it." It didn't detect Windows 7 as it did before and wanted me to start as if the entire disk were blank. It asked if I wanted a "new partition table" or "edit the current partition table." Therefore, I cannot install Xubuntu in dual boot with the current windows 7 installation? Would anyone be able to explain why Xubuntu installer is not detecting the Windows 7 partition, and what I can do to correct the issue so that I can install Xubuntu? Thank you.