Sounds like you have some problems with the set up of your machine. Have you tried installing a clean version 5.21 !Boot? Once that is running ok with the older ROM it should be ok to move to a newer ROM at some point. Then add back in to !Boot stuff which is absolutely essential to be in !Boot. (I know you are a bit of a hacker so this is the sort of thing you will have done at times in the past anyway). I keep my !Boot as clean as possible, running as little extra as possible. Once the machine is in the desktop, then I normally run an obey file to set up my 'core' apps etc. This way changes to Apps, what apps are run etc do not affect the boot process itself. With regards to these specific tests, Fat32Fs is run from PreDesk during boot. SparkFS is not run during boot, so I can run that at any time (although normally it would be one of my 'core' apps run from the obey file once the machine was up). For most of these tests no other apps had been run so it was a pretty clean machine. I will have a further play later, including modifying the pen drive on the BB or Iyo between attempts to crash things. Are you doing a full quit of SparkFS between the various copying of files? -- Chris Johnson --- To alter your preferences or leave the group, visit //www.freelists.org/list/armini-support List-related queries to info@xxxxxxxxxxxx