Hi, Im new in this forum, hope you guys can help me out, I usually build my own PCs but I dont really have that much experience, specially not with HP PCs. So, I took my own SATA HDD to my cousins home, I installed it, but since I forgot to bring my own power adapter, I unplugged my cousins secondary HDD. Anyways there was no problem, my HDD was recognized, I got the READY FOR USE message, and well I got the files I needed. After I was done with that, I took my HDD, plugged back his own secondary HDD and the bios recognized it. Then we go into windows, it loads, no problem, but the secondary HDD is not recognized, it just wont show on windows explorer or anything. This is an old PC, its a Pentium D, and its an HP model, media center windows XP, it has a different type of windows bar. I dunno I hate the interiors its so hard to reach everything. Does matter where I plug the sata cable? I never had this problem before with sata HDDs. I went to the Bios and saw both HDDs as recognized, they even show as functioning hardware on windows control panel/add hardware. I´m just confused that I couldnt make it run, but to be honest I didnt have time to work on it cuz I had to leave, actually I just got home from his house, and Im going tomorrow to try to fix it. hope you guys can help, or give me any clues on what I can try to do tomorrow. bye.