Running W7 Ultimate and recently in My Computer, Local Disk (Q:) shows up with blank total size and free space. Checking Disk Management, no such disk shows but the letter Q is not available in the drop down list for changing drive letters. Any suggestions as to the registry entry(s) that might be responsible for this? Of course attempting to open or check properties of Q results in "Q:\ is not accessible. Access is denied." TIAtheWeissGuy

Are you using Bitlocker or have ever used Bitlocker? http://support.microsoft.com/kb/928201 Note: The BitLocker Repair Tool is included by default in Windows 7, and it does not need to be downloaded separately. You can go directly to step 4 in the article and see if you can use the tool to decrypt the data.You could also have a laptop drive Q: “Lenovo_Recovery” Did the driver letter have a volume name to it. MCSE, MCSA, MCDST [If this post helps to resolve your issue, please click the "Mark as Answer" or "Helpful" button at the top of this message. By marking a post as Answered, or Helpful you help others find the answer faster.]

Are you running any VM software (be it XP Mode, the App-V client, VPC, or whatever) installed on that PC?Possibly the Office 2010 Beta?[If this post helps to resolve your issue, please click the "Mark as Answer" or "Helpful" button at the top of this message. By marking a post as Answered, or Helpful you help others find the answer faster.]

Chris - only VM software I use is VMware workstation. I am using Office 2010 Beta. I'm not using bitlocker and this is a desktop system, not a laptop. There is no volume name associated with Q. Any further suggestions?theWeissGuy

". I am using Office 2010 Beta."And, that's where your drive Q came from. It's a virtual drive that's used by the click-to-run function. Just Google office 2010 drive Q for a lot of articles/comments/details on it.HTH,Chris[If this post helps to resolve your issue, please click the "Mark as Answer" or "Helpful" button at the top of this message. By marking a post as Answered, or Helpful you help others find the answer faster.]