The default username & password for IPsession WUI is "Administrator"  & "admin", please try and see if you can login.

Further if are not able to login through that you can reset the "Administrator" password by running the batch file on IPsession server. the path of the batch file is 

"C:\IPcelerate\IPsession\bin\httpssetup.bat"

Let us know if this helps you to login to IPsession WUI.