Maxthon is a browser that uses both the Trident ( IE ) and Gecko ( Firefox ) browser engines. This browser is available in a portable version, and this quick tip is about how to resolve an issue when opening Maxthon Portable, and it gives you an error saying "Another instance of Portable Maxthon is starting. Please wait for it to start before launching again" ( it should also apply to most cases when you receive an error upon starting the program ).
To resolve the issue, go to the Portable Maxthon folder > Data and look for a file named PortableApps.comLauncherRuntimeData-MaxthonPortable.ini. Delete this file ( don't worry, it will be recreated once Maxthon has successfully opened ) and then try to start Portable Maxthon.