I downloaded the 64bit Windows installed for "Tor Browser" from this URL

https://www.torproject.org/download/download-easy.html.en

It installed and worked as expected and can display normal and .onion sites.
The first default page it displays is  `about:tor`
Under "you can help" there is a link called *[Run a Tor Relay Node][1]*
which says

>Alas, since Vidalia (a graphical interface for Tor) is no longer included in Tor Browser, there are currently no easy relay packages for Windows and OS X users.

followed by *Configure Tor by editing the torrc file*.

I edited my `..\Tor Browser\Browser\TorBrowser\Data\Tor\torrc` file as directed and added the port forward to my firewall.
Unfortunately the Tor Browser failed to start after that and entered a `failed to start, need to restart` loop.

I enabled debug logging but nothing was added to the log during these events.
I reverted the edits and verified the logging system actually worked.
I trawled the tor site, Google and this site for further explicit information with no luck.

I am now assuming that the "Tor Browser" is 100% client and cannot relay traffic for any other users of the network. 

Am I correct ? and if not, how do I active the relay functionality.
Thanks.

**Clarification**

I understand and followed the instructions on the Tor site. What I don't know is if they failed because they were *never intended to work on the Tor Browser* or for some other reason.


**in response to  Jens Kubieziel requests for more detailed test ....**

start with Tor Browser closed

contents of "S:\tor\Tor Browser\Browser\TorBrowser\Data\Tor\torrc" are

    # This file was generated by Tor; if you edit it, comments will not be preserved
    # The old torrc file was renamed to torrc.orig.1 or similar, and Tor will ignore it
    
    DataDirectory S:\tor\Tor Browser\Browser\TorBrowser\Data\Tor
    GeoIPFile S:\tor\Tor Browser\Browser\TorBrowser\Data\Tor\geoip
    GeoIPv6File S:\tor\Tor Browser\Browser\TorBrowser\Data\Tor\geoip6

add this line at bottom

    Log debug file my_debug.log

save and close

open Tor browser and goto Tor blog page, all Ok.
close Tor Browser

a file has been created at "S:\tor\Tor Browser\Browser\my_debug.log" with 32000 odd log entries.

change contents of "S:\tor\Tor Browser\Browser\TorBrowser\Data\Tor\torrc" to 

    # This file was generated by Tor; if you edit it, comments will not be preserved
    # The old torrc file was renamed to torrc.orig.1 or similar, and Tor will ignore it
    
    DataDirectory S:\tor\Tor Browser\Browser\TorBrowser\Data\Tor
    GeoIPFile S:\tor\Tor Browser\Browser\TorBrowser\Data\Tor\geoip
    GeoIPv6File S:\tor\Tor Browser\Browser\TorBrowser\Data\Tor\geoip6
    
    Log debug file my_debug.log
    
    ORPort 443
    Exitpolicy reject *:*
    Nickname 78629847569874
    ContactInfo [email protected]

save and close
    
deleted contents of "S:\tor\Tor Browser\Browser\my_debug.log"

open Tor browser 

get following error message

![enter image description here][2]

check contents of "S:\tor\Tor Browser\Browser\my_debug.log", its blank

click "Restart Tor"

get following error message

![enter image description here][3]

check contents of "S:\tor\Tor Browser\Browser\my_debug.log", its blank

Try the "Copy Tor Log To Clipboard" button and paste into notepad, also blank.

click "Restart Tor"

get same error message

logs still blank

click exit

get following error message

![enter image description here][4]

click OK

check contents of "S:\tor\Tor Browser\Browser\my_debug.log", its blank


  [1]: https://www.torproject.org/docs/tor-doc-relay.html.en
  [2]: https://i.sstatic.net/w4Gpa.png
  [3]: https://i.sstatic.net/qjKfk.png
  [4]: https://i.sstatic.net/AGOcK.png