dual boot - GRUB does not detect Windows

I have finally installed Ubuntu on my second drive. When I start my computer GRUB only offers me to boot Ubuntu, not Windows 7. What needs to be done so that I can choose between Ubuntu and Windows in GRUB?

When I press F12 for boot menu at startup and I choose Windows Boot Manager it boots into Windows 7.

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I ran command sudo fdisk -l and here is log (http://pastebin.com/Cgv1igHc):

WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted.



Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0xc3ffc3ff

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1  1953525167   976762583+  ee  GPT

Partition 1 does not start on physical sector boundary.