How to get the default modelsim.ini file back？

I compiled the libraries of FPGA and get a new modelsim.ini file in complied directory. Then I directly copy this file into modelsim installation directory. The default one has been replaced. Then I found this is a bad choice since in default modelsim.ini file, it has information for default libraries directory. So I wonder how can I get the default modelsim.ini file back？