After using an external hard drive with Windows 7 (Prof), it stopped to be recognized in any Windows XP (Prof), telling (in XP that it is not formatted and should be formatted for using), though it is usable (the data is readable and writable) in any Windows 7.

What's happened and how to make it again usable in Windows XP?

Update:

When it is plugged in Windows XP, the light is on, the HDD is spinning and I am informed that: "O:\ is not accessible.

The file directory is corrupt and unreadable"

Just searched internet for its description. Since I've bought it 6 years ago It corresponds, by the image to Maxtor Basics Portable 250GB USB2.0 2.5inch External Hard drive - STM902503EHD301

I have run more than once chkdisk on it from Windows 7.

There are a lot of threads about it "stopped responding" on the internet without any solution

After using an external hard drive with Windows 7 (Prof), it stopped to be recognized in any Windows XP (Prof), telling (in XP that it is not formatted and should be formatted for using), though it is usable (the data is readable and writable) in any Windows 7.

What's happened and how to make it again usable in Windows XP?

Update:

When it is plugged in Windows XP, the light is on, the HDD is spinning and I am informed that: "O:\ is not accessible.

The file directory is corrupt and unreadable"

Just searched internet for its description. Since I've bought it 6 years ago It corresponds, by the image to Maxtor Basics Portable 250GB USB2.0 2.5inch External Hard drive - STM902503EHD301

I have run more than once chkdisk on it from Windows 7.

There are a lot of threads about it "stopped responding" on the internet without any solution

Update2

Driverwhiz and DriverPack Soltion 13 show that there are no uninstalled drivers.

Segate DicWizard proposes to delete all pertitions (which is not new as it is proposed by Windows XP though Windows 7 reads OK), though detects it as ST9160821AS 150GB

Checked in Windows 7 that it is formatted as NTFS and BitLocker is turned off

After using an external hard drive with Windows 7 (Prof), it stopped to be recognized in any Windows XP (Prof), telling (in XP that it is not formatted and should be formatted for using), though it is usable (the data is readable and writable) in any Windows 7.

What's happened and how to make it again usable in Windows XP?

After using an external hard drive with Windows 7 (Prof), it stopped to be recognized in any Windows XP (Prof), telling (in XP that it is not formatted and should be formatted for using), though it is usable (the data is readable and writable) in any Windows 7.

What's happened and how to make it again usable in Windows XP?

Update:

When it is plugged in Windows XP, the light is on, the HDD is spinning and I am informed that: "O:\ is not accessible.

The file directory is corrupt and unreadable"

Just searched internet for its description. Since I've bought it 6 years ago It corresponds, by the image to Maxtor Basics Portable 250GB USB2.0 2.5inch External Hard drive - STM902503EHD301

I have run more than once chkdisk on it from Windows 7.

There are a lot of threads about it "stopped responding" on the internet without any solution