XP Ho won't see the other drive where Windows 7 is installed (in dual boot)

[edong]

Windows XP Home SP 3 - 500GB Western Digital
Windows 7 Premium - 1 TB Seagate

Been using dual boot for almost a year by pressing F9 to select the boot device. My problem began when XP caught the 'fakerean' malware. When removed, I got blue screen whenever I choose XP to boot. Could not boot even in Safe mode. Windows 7 was okay.

Then I disconnected the Windows 7 hard drive. For some reasons, XP was able to run in Safe Mode and was able to do a System Restore. Then I ran 'chkdsk /f' and 'malwarebytes' and everything looked fine again at least with only one drive

When I re-connected the Windows 7 hardrive(Seagate), I can still press F9 and boot with Windows 7 and see both drives and all their partitions. BUT if if I choose Western Digital and boot with XP, I don't see the Seagate hard drive. Other than that, XP looks okay again. Many of the programs I am using are installed in XP and just saving the data in Seagate.

Any idea of a tweak? Before the problem, if I don't press F9, it will boot to Windows 7 by default. Now it's defaulting to XP. I could not find an answer on google. Thanks.

[davexnet]

Logon to XP and use the command diskmgmt.msc.
It should reveal to you info about all the drives in your box.

[edong]

I did that. Like in My Computer and Explorer, it only shows the 2 partitions of Western Digital Drive (C & D) and 2 DVD drives. Like I said, when booting up, I can choose the Seagate and boot to Win 7 and see both drives and all partitions. Perhaps something in the XP serial controller was messed up.

Thanks.

[davexnet]

Is the missing device visible in XP's device manager (under "Disk Drives") ?
If not, I suspect something in the BIOS or possibly a cable is bad.

To enter the device manager, enter the command devmgmt.msc