Accidental deletion of the Rundll32.exe file results in the consequences

Accidental deletion of the Rundll32.exe file results in the consequences
All applications are not open.
Workaround:
1. Go to C:/windows/system32 and find Regedit.exe and change it to regedit.com.
2. Run Regedit in the beginning
3. Locate/hkey_classes_root/exefile/shell/open/command and modify the default data to "%1"%*
4. Then go to My Computer---> Menu tools----Folder Options----File type-----New extension EXE, point advanced Select Application---OK
5. Prepare Rundll32.exe
6. Register Rundll32.exe: Run the input rundll32.exe C:/windows/system32/rundll32.exe

If the rundll32.exe is mistakenly deleted, follow the above 4,5,6 steps can be done.

If it is poisoned, exe associated file fails:

Please follow the steps to solve