ComDiag 4.0 detects and displays the real device names of all connected serial port devices.

When you have a number of different types of Plug and Play device displaying the real 'friendly' name is much better than simple 'DOS' names such as Com1, Com2 etc.

During the test ComDiag displays progress bars and test results as soon as each of the individual tests is complete.

As well as checking the transmit and receive capability it also checks all flow control, ready and other signals such as DCD/CD (Carrier Detect) and RI (Ring Indicator)

At the end of the test ComDiag also detects installed device drivers of any inactive ports. For example USB or other removable devices which are currently missing but could become active when you power up or connect the relevant hardware.