absic115, let me answer as follows <>:
You have an external Blacx ST0005U that works OK with USB.
<Correct>
If you connect it to the e-SATA port(s) on the back panel of your Mobo the HDD is recognised when you cold boot your PC but you can't hot swap.
<Correct it only recognized in IDE mode but not RAID or ACHI>
When you tried this did the PC Crash?
<No, did not crashed.>
Did you try Scanning for New Hardware?
<No, haven't done that and don't feel the need to do that for awhile.>
Have you tried using the Driver from Thermaltake:
http://www.thermaltakeusa.com/Product.aspx?S=1268&ID=1731#Tab4 and does it make a difference?
<have not used the driver from TT. From what i can tell, it's for WinXP and Vista, not for Win 7 that I am running on. Trying the driver in Win 7 will probably not be a good idea.>
You have tried setting the e-SATA channels in BIOS to AHCI and also RAID but still no success.
<Correct.>
Do you get the Safely Remove Hardware icon when you try this method?
<couldn't remember but rearely used the "Safely Remove Hardware" function. No harm observed thus far
>
Is the HDD recognised in My Computer?
<No, did not recognized.>
Does using the Thermaltake driver work?
<see above.>
When you connect via e-SATA you did remember to disconnect the USB cable? (A Simple thing to forget about)
<YES!>
You have tried setting both the GSATA and e-SATA channels to AHCI but this caused you problems because you have already installed your OS in IDE Mode and even trying the Registry Hack failed to get your system to BOOT.
<DITTO>
Would it be possible to re-install your OS in AHCI mode? This option has to be weighed against the need for e-SATA to work. It might be better to leave it until you have to re-install the OS especially, if like me, you have a lot of large programmes.
<yes, O/S re-install will be my last resort to reap the benefit of ACHI and eSTATA. Maybe not as much as you, but i have decent amount of large programmes.>
Sorry about going through this again but sometimes it is better to stand back, go through the steps and processes taken so far, just to make sure we are all singing from the same hymn sheet.
<no problem, thanks for trying to help.>