When a scan is running and the scan progress is shown, both the x86 & x64 versions in Windows Vista SP1 & Windows 7 Beta 1, the log window will appear all blank after some time. This can be "fixed" by dragging the window off-screen (eg: below the task bar) and restoring it on screen. It doesn't seem to make any difference is scroll log is ticked or not. All 3 PCs have Aero enabled (may be an Aero specific bug) and all are running the latest drivers for their respective nVidia/ATI/Intel (integrated) graphics. This bug/issue was also apparent in v3.