id summary reporter owner description type status component version resolution keywords cc guest host 11426 VBox 4.2.x crash QtGuiVBox4.dll 4.7.3.0 and MSVCR100.dll 10.0.40219.1 Ady "I've been using VBox 4.1.x without big issues. Every time I try uninstalling v.4.1.22 so to update/upgrade to VBox v.4.2.x (every time there is a new VBox 4.2.x update), I get crashes, so I have to uninstall and downgrade back to v.4.1.22. In most (if not all) cases, VBox manager is the one crashing, not the VM. In fact, I have seen the host OS, Vista Home Basic x32 with SP2 and all Windows Updates, reporting the crash of VBox manager while the VM is still working, and I am able to finish my session in the guest. Then I don't have any choice but to close VBox (or close and send info to MS). When I downgrade to VBox 4.1.22, I keep my VMs (which are located in the same physical HDD but in a different partition than the VBox manager program). So when I re-install v.4.1.22, I can use the same exact VMs as with v.4.2.x, and there are no crashes. I have seen other forum topics and bug tickets regarding QtGuiVBox4.dll and/or MSVCR100.dll, but they are either (too) old or seem to me not exactly related to the behavior I am seeing with VBox 4.2.x. I have also tried with less RAM assigned to a VM, and with different types of guests (from FreeDOS to several Linux LiveCDs and to Linux installations as guests), and the crashes occur almost always. If there is a specific preference or setting I should be changing or testing, please let me know. I have also been posting reports at [https://forums.virtualbox.org/viewtopic.php?f=6&t=51889] Maybe the following info might be useful, as it repeats itself (specially the one about QtGuiVBox4.dll): {{{ Product Oracle VM VirtualBox Manager Problem Stopped working Date 2013Jan26 13:26 PM Status Report Sent Problem signature Problem Event Name: APPCRASH Application Name: VirtualBox.exe Application Version: 4.2.6.0 Application Timestamp: 50d1d0ed Fault Module Name: QtGuiVBox4.dll Fault Module Version: 4.7.3.0 Fault Module Timestamp: 50085702 Exception Code: c0000005 Exception Offset: 0016bee3 OS Version: 6.0.6002.2.2.0.768.2 Locale ID: 1033 Additional Information 1: f61b Additional Information 2: 2eef8746f809bffc851f433fa3a47dc3 Additional Information 3: 5513 Additional Information 4: 9d9ceca6bad9b1aad2812fa32f91fde9 }}} {{{ Product Oracle VM VirtualBox Manager Problem Stopped working Date 2013Jan25 19:22 PM Status Report Sent Problem signature Problem Event Name: APPCRASH Application Name: VirtualBox.exe Application Version: 4.2.6.0 Application Timestamp: 50d1d0ed Fault Module Name: MSVCR100.dll Fault Module Version: 10.0.40219.1 Fault Module Timestamp: 4d5f0c22 Exception Code: c0000005 Exception Offset: 00010a40 OS Version: 6.0.6002.2.2.0.768.2 Locale ID: 1033 Additional Information 1: 5bc5 Additional Information 2: 40f9f5a8af0ca8da6f1b3003e39b55c1 Additional Information 3: 0e1d Additional Information 4: 563fa9434bb661b960ec2f78bcc92833 }}} And, as said, when going back to VBox 4.1.22 each time, there are no crashes. They re-appear every time I update VBox to a new v4.2 release. I'm attaching VBox logs. Please advice. TIA, Ady." defect closed other VirtualBox 4.2.6 obsolete QtGuiVBox4.dll MSVCR100.dll other Windows