So I had Windows XP on another disk volume, and tried removing that volume when I created the RC and merging with another partition on that same disk. So I end up with 1 entire unpartitioned disk. So far so good. Then I try creating a disk, and testing out the dynamic disks, I converted the disk to dynamic. Then trying to see what offline does, I set that disk (disk 0) to offline. It was completely removed from my disk management view, so I was unable to get it to come back online. I had to use the diskpart utility, to get the disk to show up in my list again, however I was unable to do anything to that disk, and basically had to format, partition, activate and create volumes on that disk from disk part before it was usable by the Disk Management utility. There should be better integration between these tools. Most users won't be comfortable with the command line tools. Although I must say diskpart and the windows help utility is reminding me more of trusted Linux command line tools, that actually do what I expect them to do. Kudos to the diskpart team.

Same problem. How do i make the disk appear in the list again? I set it to offline thinkign i might be able to mirror it, ( hoped in vain) alas i restarted and now the disk sis nowhere to be seen.!! tried DISKPART SELECT DISK 2 ONLINE LIST DISK then reports errors.. I hope a restart solves this.

I just did the same thing as you both.frantyk, just type 'diskpart' in the CMD window and hit enter you will get into the diskpart system. Then typehelp.Ok, went like this. In disk manager, I converted an empty hard drive to dynamic. Then, without creating a volume or anything, I offlined the disk. The 'Offline' menuitem never switched to 'online'. So, off into Diskpart I go. I had to use the 'Rescan' command to get the disk to show up again, since 'list disk' didn't show it. However as soon as I did rescan, an autoplay window popped up. The disk was back. I was able to 'Online' it there. I tried to convert it back to a basic disk, but that wouldn't work. Pause for disclaimer:Please note that the instructions for diskpart that I could find like this, clearly state that you must delete any volumes before you can convert to a basic disk, so yes, you would lose all information. I had no data on the drive before the conversion to dynamic... So I lost nothing except time.Ok, so after reading that, I deleted the volume. Then the 'convert basic' command worked fine. The rescan command made it show back up in the disk management gui, however I could not do anything except dynamic commands on it. So back to the CMD window, and created a primary partition. Now, the disk management gui sees it, lets me format it and assign a drive letter.So, wasn't the smoothest transitioning from one to the other. I suspect it might have been better if I had created the volumes or whatever before I offlined it. However I was able to recover it. All in all, about the same experience as KappaMax. Further, I hope this helped you frantyk.

The DISK ONLINE did work, but the disk now shows "Online, with errors". :( The disk was Dynamic before i set it "offline". I want to save all the data on it so hopefully when i get home i can try your method out to at least get it to show the disk in the list. I dont really want to clear the partitions on it as the data is important. Any ideas on how to fix a "online with errors) problem? Thanks

frantyk,Any luck with getting your data back? As mentioned above, I had no data on the drive... so I didn't try to correct the error state. I never actually did anything with the drive such as format it.

frantyk,Did you have any luck? I see you said Thank you in a thread about a read only drive... was that this issue?