#2 Process ExplorerProcess Explorer is a great tool for digging into open files or resources. Trying to open a file, but getting a notification that it is already open? Process Explorer can help determine which application or process has the file open. It is a GUI-based utility and can be used as a task manager replacement. The utility has two panes of information, the top pane shoes currently active processes on your system and includes information about the name, the account that owns the process, and the CPU usage of the process.
The bottom pane of Process Explorer has two modes of operation, handle mode and DLL mode. When handle mode is enabled, selecting a process in the top portion of the window will show you the handles that the process has open. In DLL mode the pane displays the DLLs and memory mapped files loaded by the selected process.
Derek Schauland has been tinkering with Windows systems since 1997. He has supported Windows NT 4, worked phone support for an ISP, and is currently the IT Manager for a manufacturing company in Wisconsin.