Add punctuation: He went to live in the mountains and only maintained a post office box as a link with the outside world
A: He went to live in the mountains and only maintained a post office box as a link with the outside world.

Add punctuation: For the last five put on a higher tone than theirs
A: For the last five, put on a higher tone than theirs.

Add punctuation: Uninstallation As DLL files are created to support other programs and softwares working well the data and functions are actually shared by many programs when you uninstall a program SystemPropertiesAdvancedexe may be mistakenly deleted
A:
Uninstallation: As DLL files are created to support other programs and softwares working well, the data and functions are actually shared by many programs. when you uninstall a program, SystemPropertiesAdvanced.exe may be mistakenly deleted.