Hard Disk Monitoring

I have a 2TB drive its like a year or 2 old and I'm using it as a bckup drive for data which means I just fill it full of files and unplug it until I need a files off of it. But in the process of putting data on it it was almost 3/4 's of the way full then all of a sudden the data stoped transferring. Then I checked HDSen and it told me to remove all data and replace the drive. I did just that moved all the data off of it and off the drive that was failing for me to use that drive. Now the drive is empty and at this point the drive is being stated in HDS as bad then good then bad then good. I do a read test on it and it does the same thing. reading good then bad then good now half way through the read test by HDSen i stop it and do a Win disk check now its reading 100% but the drive letter is not showing now I'm doing another read test to see whats it gonna do.

What should i do trough the dive away or trust it again.

According the information you wrote, the drive may sometimes provide incomplete status information about itself and this causes confusion: as you saw, sometimes it seems perfect, but when when the complete status reported, it is reported as bad.

This fluctuation (especially if happens so quickly) sometimes can be caused by communication issues (eg. data cable problems) or even power-related problems (for example problem with power supply if this is external drive has a separate small power supply).

The best would be to know some more information about the drive, for example the complete text description (when the drive reported as bad), to see the actual number and type of errors displayed. Also it would be nice to check the complete status as it may confirm the above.
Please use Report menu -> Send test report to developer option about the drive. If possible, please do it two times: when the status seems to be bad and when it seems to be correct - as even this difference can point on the actual problem with this hard disk.

Personally I'd not really trust the drive now (at least before we check actual status with more details).

I sent two before and not at 3:18 pm today 1-20-11 and the drive is a external on a thermal tale 2 port drive

Thanks, I checked the reported information about the drive.
As suspected, some kind of information reported incorrectly. Namely, the manufacturer-defined error-threshold values (the "Threshold" column on the S.M.A.R.T. page) for the affected drive is reported incorrectly (you may check: these values should never change for a drive but I suspect you may see them changing randomly).

This can cause a false assumption that the drive sometimes reaches the thresholds (when error is reported) and sometimes not - while the drive seems to be working relative correctly.

This issue (as I wrote previously) may not indicate real failure of the drive, but can be caused by communication issues, exactly as you can see in the "Text description": Problems occurred between the communication of the disk and the host 2785 times.

So I'd recommend to check (and maybe replace) SATA data and maybe power cables (eSata in this case if the drive is in external device) and verify if this error-counter will stay at this level (and no false information reported) or if you still experiencing problems. For a test, you may try to directly connect the drive to the motherboard (as in some rare cases even the external enclosure can cause such communication issues).

Another thing which may cause such incorrect information is the driver for the hard disk controller. As I see, now it is working with "Standard Dual Channel PCI IDE Controller (ATA)" driver (see Information page). This may not working correctly for all controllers, you may try the proper drivers provided by the manufacturer.

You may send new report(s) any time if you see some changes - so I can check the differences and may advise.