Failure code: gb_genlog(175) after GoBack window. I tried all KB articles on Symantec side and at many forum sites. Uninstalling or repairing gb_prog.exe does not work at all. After it starts, gives same error with code # "181. Not able to reach SATA HDD with bootable DOS diskettes. What else can I do? There must be a way to bypass GoBack.

Have you tried reinstalling GoBack? Before you do, make sure you type %TEMP% in the Run window (to delete all the files in the temp folder).
Also deselect all the start up's (msconfig), in the run window.

If that doesn't work, try booting into safe mode by tapping the F8 key during bootup. Then un-install GoBack, reinstall. Then boot back into normal mode and retest.

Not possible to reach Run window. Also when I could not reach windows menu by F8. Only gives me bootup sequence menu and after I choose HHD, GoBack starts immediately.

Why are you running GoBack? Windows XP provides "System Restore" (does same thing). When you installed this software, it takes control of what happens during and after bootup. I'd remove it if I had to do it manually. Windows XP cannot take control of the machine and how it runs as long as that software is running. Get rid of it it even if you have to start from scratch and format the hd. Since you chose to use this software, you have to live with it (or learn how to deal with it). Doesn't Symnatec offer any technical help either by phone or website?
About all I can suggest is to do a lot of reading.