Hi All, being a control freak I always enable case sensitivity on my Macs. The Mac OS X file system has optional case sensitivity, insensitive by default. I once got burned with a check-out where one directory overwrite another and chose sensitivity from then on. This has caused a few problems over the years, including a Flash update that failed. No matter. Squeak has FileDirectory class>>isCaseSensitive answer a hard-coded boolean. Not good. I see this from stackoverflow<http://stackoverflow.com/questions/430256/how-do-i-determine-whether-the-fil...> : "Keep in mind that you might have multiple file systems with different casing rules. For example, the root filesystem could be case-sensitive, but you can have a case-insensitive filesystem (e.g. an USB stick with a FAT filesystem on it) mounted somewhere. So if you do such checks, make sure that you make them in the directory that you are going to access. Also, what if the user copies the data from say a case-sensitive to a case-insensitive file system? If you have files that differ only by case, one of them will overwrite the other, causing data loss. When copying in the other direction, you might also run into problems, for example, if file A contains a reference to file "b", but the file is actually named "B". This works on the original case-insensitive file system, but not on the case-sensitive system. Thus I would suggest that you avoid depending on whether the file system is case-sensitive or not if you can. Do not generate file names that differ only by case, use the standard file picker dialogs, be prepared that the case might change, etc." Luckily this is only tested in a couple of places. Most of the time the system resolves names by going through primDirectoryEntryFor: which leaves it up to the individual file system to decide (and hence get the answer right). I wonder what does FileSystem do about this? -- best, Eliot