Do not open nothing here

Question

accidently posted two of the same thing

Answer 1

You cannot just pass an html file to the command line from a form and expect it to launch a browser. Either of the following should work, but keep in mind there are many additional ways to accomplish this.
OPTION 1:
This method is intended to handle web content and URLs. This is not the best choice for other content types.
client_host('rundll32 url.dll,FileProtocolHandler "c:\TOC.htm"');
OPTION 2:
This option is probably the better of the two because it will properly handle any document file extention. In other words, if you try to open a .doc file and MS Word is installed, it will automatically open it. If a .txt file is entered, it will automatically choose Notepad.... and so on.
client_host('rundll32 shell32,ShellExec_RunDLL "c:\TOC.htm"');