No, we cannot use two instances of UFT on the same machine. However, UFT handles multiple instances of the application that is going to be tested.
We can even work on two different applications on the same machine without stopping the recording of UFT. For this, you need to modify a few configuration settings of the UFT.
You need to select the option “Record and Run on any opened application” from Automation -> Record and Run settings -> select.
For Example, UFT can work on multiple windows of IE browser.