id summary reporter owner description type status component version resolution keywords cc guest host 3076 VirtualBox 2.1.0 silently fails guest file opens when VBox process runs out of file descriptors Paul "Performing some large Visual Studio builds on Windows 2003 using a project located in a shared folder was failing with random windows errors about being unable to open specific files. The files named existed and could be opened at a later time with no problems. On a hunch, I increased the ulimit of file descriptors from 256 to 1024 and restarted the virtual machine. After then I was able to use VStudio without errors. (I was also able to reproduce the error by attempting a Windows command line copy of the project with ""xcopy /s "") It would be helpful if when VirtualBox encounters EMFILE errors to log a notice (rate limited if need be) to the log file for the machine to give a hint as to the problem." defect closed shared folders VirtualBox 2.1.0 fixed Windows Solaris