Im so happy & relieved today...I got the E:, F:, G:, and H: drive back again! I've disabled them in the past(now I remember) via the Safely Remove Hardware icon in my Notification Tray. In my desire(in the past) to minimize the icons that are shown in the Notification area I've double clicked on the Safely Remove Hardware icon and on the window that appeared I click on Properties(re: USB Mass Storage Device) then on the window that appeared I choose to disable Device Usage. This leads to disabling of the other drives(E F G H) in my pc. I only intend to disable the Safely Remove Hardware program&icon at that time. Now this morning, prompted by latest DavidR's suggestion to check for any disabled service(s), when I go to Control Panel>Administrative Tools>Services> I noticed that Removable Storage is "disabled"...so when I right clicked on it today and under Properties choose "Automatic" in Startup Type then "start" the service all the previously "missing" drives (re)appeared in My Computer>Manage>Disk Management. Anyway, all is well now and i can now have peace of mind knowing that my pc is in good(if not excellent) working order. Lesson learned...I now intend to keep a diary of all the changes in the configuration & settings that I'll be doing in my pc. Thank you very much and im sorry for all the hassle that I've given you.
By the way, can I get rid of the Safely Remove Hardware icon without disabling any drives? Or do I have to see it forever in the Notification Tray.