I chose "all tasks shutdown" and started Ice Clean 3.1.2 on 6/24/11 at about 11am. It is now 06/25/11 at 5pm and Ice Clean has, apparently, not completed the tasks and shutdown my MacBook Leopard 10.5.7. So IceClean has still not stopped running over 30 hours later. The circle in the lower right corner of the IceClean interface window is still moving around. The only thing I did differently compared to previous times, when I have run this version of Ice Clean without this problem, is I forgot to dismount and disconnect my USB external 1 TB Iomega drive. In fact, I usually disconnect all USB peripherals when I run IceClean. I think the Iomega drive has about 700 GB of information on it including at least 2 separate full backups(clones) of my MacBook's internal boot drive. I have never before run IceClean without first dismounting and disconnecting any external USB drives and I have never run disk repair or verification on any of my external USB drives. Activity monitor does not say IceClean is "not responding" and, when I INSPECT IceClean statistics with Activity monitor, the 3 mach numbers, the unix number, and context switches number are constantly changing(increasing). The %CPU is also changing constantly and it has ranged between about .92 and 1.60. When I right click the IceClean icon in the Dock it says "Application Not Responding". And when I click on the IceClean interface the toolbar/menu bar does not switch to IceClean; although, I can drag the IceClean interface window around the monitor screen. I am not sure, however, if the developer intentionally configured IceClean to be unresponsive in the dock and interface, while it is still running, in order to prevent users from shutting IceClean down while it is running, which the developer states can be "seriously dangerous for your system". I have not force quit IceClean because the IceClean interface and the developer's website says "Don't force IceClean to quit: that could be seriously dangerous for your System." Should I force quit IceClean? Many hours ago IceClean INSPECT in Activity Monitor did indicate 1 recent hang, but now it says 0 recent hangs. I do not know what to do. I do not understand what IceClean 3.1.2 is doing. Is it "not responding" or is it still working normally? Is it trying to do work on the 1 TB Iomega drive that I forgot to dismount and disconnect before running IceClean? Should I dismount and disconnect the 1 TB Iomega drive now in order to get IceClean to stop running? Temperature Monitor App shows my MacBook's CPU A temperature at 60 degrees C with 4 Firefox 5 windows and multiple tabs open. I usually stop using my MacBook while IceClean or Disk Repair is running, but when IceClean had not stopped running 8 hours later, yesterday, I felt I had no choice, but to start using my MacBook while IceClean is running. In fact, I have connected to the Internet with my MacBook in order to send you this email message. The IceClean developer website is http://www.macdentro.com/MacDentro/Home.html and I have sent an email to the support address at that website. There does not seem to be a user support forum on the macdentro.com website. I have searched on the Internet for instances where other IceClean users have had the same problem I am now experiencing, but I have not been able to find any. ------ Purpose Of This Thread I am seeking a reply from someone who clearly understands the technical aspects of how IceClean works and who can, therefore, tell me what steps to take to determine what exactly IceClean is doing, if anything, to my MacBook system right now, who can tell me how to determine if IceClean is "hung" and "not responding", and who can tell me what actions I can take, if any, to safely force quit IceClean. This thread was started as a means to seek a reply from someone who expertly understands the technical aspects of how IceClean works and who will, therefore, answer certain questions the thread starter has with regard to the application. If that is you, then, please reply. If that is not you, or you do not use IceClean, you do not want to use IceClean, or you feel IceClean should not be used, then, I ask that you not reply, because your input is unlikely to be compatible with this thread's purpose.