Hi, You are not alone ;) I have exactly the same problem on a HP laptop with Vista SP1 (french) and whatever version of DrScheme. On my XP SP2 or SP3 though, there is no problem. Laurent <div class="gmail_quote"> On Wed, Dec 9, 2009 at 05:01, Benjamin L.Russell <<a href="mailto:DekuDekuplex@yahoo.com">DekuDekuplex@yahoo.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> This is just a polite, but detailed, bug report reporting the results of trying out DrScheme v4.2.3 on a different computer than before (a laptop this time), with a different set of drivers installed, running the same version of the same OS on which the intermittent file explorer hanging problem had appeared before. (For those new to this issue, the "intermittent file explorer hanging problem" mentioned above (first reported in the thread "annoying hanging behavior when saving files on DrScheme version 3.99.0.13-svn26feb2008, english" [1] (see <a href="http://list.cs.brown.edu/pipermail/plt-scheme/2008-March/023922.html" target="_blank">http://list.cs.brown.edu/pipermail/plt-scheme/2008-March/023922.html</a>), and subsequently reported in the threads "Any tips for avoiding intermittent freezing when navigating file system directories with mounted network volumes in DrScheme?" [2] (see <a href="http://list.cs.brown.edu/pipermail/plt-scheme/2008-August/026608.html" target="_blank">http://list.cs.brown.edu/pipermail/plt-scheme/2008-August/026608.html</a>), "hint for debugging file navigator freezing bug in DrScheme 4.1.1, english, on Windows XP Professional, Service Pack 2" [3] (see <a href="http://list.cs.brown.edu/pipermail/plt-scheme/2008-October/027717.html" target="_blank">http://list.cs.brown.edu/pipermail/plt-scheme/2008-October/027717.html</a>), and "a possibility for the intermittent file explorer hanging problem in DrScheme" [4] (see <a href="http://list.cs.brown.edu/pipermail/plt-scheme/2009-March/031373.html" target="_blank">http://list.cs.brown.edu/pipermail/plt-scheme/2009-March/031373.html</a>)) refers to a bug that had previously appeared when running DrScheme v372 and later on my desktop Wintel computer (at work) running the Japanese version of Windows XP Professional, Service Pack 3, in which the "Select a file" dialog box would periodically freeze for a few seconds every eight to fourteen seconds or so while navigating through folders in a hierarchical directory. It had also previously appeared in the same dialog box when running DrScheme on another Wintel computer at a previous job, also running the Japanese version of the same OS (with Service Pack 2 then). This bug cannot be replicated on the English version of the same OS, and there had been some controversy on this mailing list and on the comp.lang.scheme newsgroup about whether this bug only occurred on my computer (the opinion of one member of this mailing list), or whether it only occurred when running the Japanese version of Windows XP Professional, Service Pack 2 or later (my opinion).) This time, I borrowed a laptop (a different computer from my desktop last time) set up by my employer (the same employer as last time) for work use at home, but running the same OS (the Japanese version of Windows XP Professional, Service Pack 2 (which I immediately upgraded to Service Pack 3)), which, according to the "System" control panel applet, has the following software and hardware specifications: System: Microsoft Windows XP Professional Version 2002 Service Pack 3 (Hardware:) Lenovo Intel(R) Core(TM)2 CPU T5500 @ 1.66 GHz 980 MHz, 504 MB RAM This computer had no mapped network drives and no shared network folders, and only had a cable Internet connection. Then I downloaded and installed DrScheme, version 4.2.3, english. However, the same bug appeared after navigating through several layers of folders in the "Select a file" dialog box that appears when clicking on the "File -> Open..." menu item. As an aside, the only other software added to all three computers that I can remember was Adobe Reader, Microsoft Office (Japanese version) (Office 2003 in the case of this laptop), Cygwin, Tweak UI (a Windows tweaking utility) (available among the "Powertoys for Windows XP"), and PLT Scheme (at least one of the versions from among v371 or later) itself. Therefore, it seems likely that this bug occurs on a given Wintel PC with this set of applications installed, running the Japanese version of Windows XP Professional, Service Pack 2 or above, when running DrScheme, English, version 371 or above, but not when running the English version of the same OS (and not just on "my computer" as has been claimed before). That's the only additional information that I have to offer right now, only because I had the occasion to borrow a company laptop. If I have the occasion to use a different computer, then I could try out DrScheme on that computer at that time as well. Has anybody else tried out the file explorer in DrScheme on a different computer also running the Japanese version of Windows XP Professional, Service Pack 2 or above? I'm the only person who uses DrScheme in my company, and my home computer is a Macintosh G4 PowerBook (currently inoperative due to defective RAM), not a Wintel machine, so I am unable to diagnose this bug on any additional computers at the present time. This bug is significant because the intermittent difficulty in navigating through directories on all three machines interrupts the flow of concentration when trying to program in Scheme in DrScheme. -- Benjamin L. Russell [1] Russell, Benjamin L. "annoying hanging behavior when saving files on DrScheme version 3.99.0.13-svn26feb2008, english." Online posting. 28 Mar. 2008. 9 Dec. 2009. <<a href="http://list.cs.brown.edu/pipermail/plt-scheme/2008-March/023922.html" target="_blank">http://list.cs.brown.edu/pipermail/plt-scheme/2008-March/023922.html</a>>. [2] Russell, Benjamin L. "Any tips for avoiding intermittent freezing when navigating file system directories with mounted network volumes in DrScheme?" Online posting. 18 Aug. 2008. 9 Dec. 2009. <<a href="http://list.cs.brown.edu/pipermail/plt-scheme/2008-August/026608.html" target="_blank">http://list.cs.brown.edu/pipermail/plt-scheme/2008-August/026608.html</a>>. [3] Russell, Benjamin L. "hint for debugging file navigator freezing bug in DrScheme 4.1.1, english, on Windows XP Professional, Service Pack 2." Online posting. 9 Oct. 2008. 9 Dec. 2009. <<a href="http://list.cs.brown.edu/pipermail/plt-scheme/2008-October/027717.html" target="_blank">http://list.cs.brown.edu/pipermail/plt-scheme/2008-October/027717.html</a>>. [4] Russell, Benjamin L. "a possibility for the intermittent file explorer hanging problem in DrScheme." Online posting. 17 Mar. 2009. 9 Dec. 2009. <<a href="http://list.cs.brown.edu/pipermail/plt-scheme/2009-March/031373.html" target="_blank">http://list.cs.brown.edu/pipermail/plt-scheme/2009-March/031373.html</a>>. _________________________________________________ For list-related administrative tasks: <a href="http://list.cs.brown.edu/mailman/listinfo/plt-scheme" target="_blank">http://list.cs.brown.edu/mailman/listinfo/plt-scheme</a> </blockquote></div>