App is not being registered in register entery

I created an test app called "notetest.exe". Then I register that app using a test.reg file. test.reg code: HKEY_CLASSES_ROOT
Applications
notetest.exe
SupportedTypes
.cpp It registered my app successfully and created a folder named notetest.exe in HKEY_CLASSES_ROOT\Applications. Then I wanted to modify the SupportedTypes (replaaced .cpp with .txt) in the code and for that I deleted notetest.exe folder. And now, the upper reg file is note registering my app anymore. File deleting process.