I got bitten by that back in 2008 - I have a blog entry (<a href="http://drschemer.blogspot.com/2008/07/plt-scheme-on-vista.html">http://drschemer.blogspot.com/2008/07/plt-scheme-on-vista.html</a>) about my problems from back then. And, I think this (<a href="http://bugs.plt-scheme.org/query/?cmd=view&pr=9554">http://bugs.plt-scheme.org/query/?cmd=view&pr=9554</a>) is the bug report with an audit trail of e-mails. I'm not sure if the installer was ever updated to know about the shadow copy. Eli and Matthew (and probably others) identified the problem. Doug <div class="gmail_quote">On Tue, May 4, 2010 at 11:46 AM, John Clements <<a href="mailto:clements@brinckerhoff.org">clements@brinckerhoff.org</a>> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">A reliable student reports to me a wild new feature of Windows Vista that interacts badly with PLT's "uninstall" functionality. Specifically, it appears that Windows has a notion of AppData\Local and AppData\Roaming that somehow shadow the files in the PLT tree, such that the following sequence of actions produces the effects described: 1) Download and install PLT 2) Using DrScheme, open and edit plt/collects/drscheme/private/debug.ss (presumably, any file in a collection would do). E.G, add the string ;;XXSECRITXX. 3) Save it. 4) using a different file viewer, see that the new file secretly got saved to AppData\Roaming *instead* of to the PLT tree. 5) Use PLT Uninstall to remove PLT. Apparently, this removes the plt tree, but *not* the secret shadowing AppData\Roaming tree. 6) Re-download and install PLT. 7) Using the new DrScheme (this is 4.2.5, IIUC), open that file again. 7) Voila! the edited file still contains the XXSECRITXX annotation, even though we uninstalled and reinstalled. Note that in the case that you make a change that prevents drscheme from starting up, this problem is much more painful. It appears to me that there are several very very bad things here, but AFAICT the only one that PLT has control over is the Uninstaller, which should be extended to delete files in AppData\Remote. Please note that this is all second-hand; Josh Robinson (cc:ed) is the one that reported this to me. Perhaps it's known and already fixed on the head? Apologies if so. John Clements _________________________________________________ For list-related administrative tasks: <a href="http://list.cs.brown.edu/mailman/listinfo/plt-dev" target="_blank">http://list.cs.brown.edu/mailman/listinfo/plt-dev</a> </blockquote></div>