Purpose With Start you can start a file such as a .exe, .bat, .doc., .pdf. The command performs the same action as a double click on the file in Windows Explorer.
Format Start "file name"

The given file is searched in the script directory unless an absolute path has been specified. Files from SAP MIME Repository are first copied to the PC (GuiXT cache folder). 

Additional Options
parameters= String with parameters
directory= Default directory
operation= Operation to be performed. Default operation is "Open". The other operations depend on the document type. Often the operations  "Edit" and "Print" are defined as well. 
prefix= The given string is put before the file name when executing the Windows start command.
suffix= The given string is put after the file name when executing the Windows start command.
returnId= If a new process is started by Start, a unique process id is returned. It can be used in TerminateProcess to terminate the process.

Please note: When you use Start to call up Excel, an already existing Excel process will be used in the standard Excel configuration. In this case no process id will be returned. You may use the Excel start option /x to force Excel to start a new process in any case. Example:
Start "&V[excelpath]" parameters="/e /r /x C:\temp\myfile.csv" returnId="proc"

Similarly, when using Start to open an image file and thus calling Photos.exe, the first call to that process leaves it active, subsequent calls do instead start self-terminating processes, to which GuiXT does not connect.
Components GuiXT + InputAssistant