Delete cookie failure

Question

I am facing a big issue with cookie.

My domain is abc.com

At the first time I login to facebook connect, facebook created a cookie at my computer as

cookie name fbs_12345
cookie value gdgdfgdf
cookie host: abc.com

Then after I logout from facebook connect. At this point I try to delete cookie by setting cookie date- 10 but fail, the only success is set cookie value to ""

Then I relogin via facebook connect again, facebook created another cookie at my computer as

cookie name fbs_12345
cookie value gdgdfgdf
cookie host: .abc.com   (with a dot in front)

At this point, I cannot access the cookie anymore, apparently it is due to cookie host, one without prefix dot, one with prefix dot

If I delete one of the cookie, then another cookie values will show out.

Any way to do a clean removal of first cookie?

.....

Function printCookie

dim x,y
for each x in Request.Cookies

  response.write("<h3>")

  if Request.Cookies(x).HasKeys then

    for each y in Request.Cookies(x)

      response.write(x & ":" & y & "=" & Request.Cookies(x)(y))
      response.write("<br />")

    next

  else

    Response.Write(x & "=" & Request.Cookies(x) & "<br />")

  end if

  response.write "</h3>"

next

End function

Answer 1

I finally found the solution to do clean removal of cookie created by facebook at my computer. Tested to work with chrome, firefox, IE8.

For my situation, set cookie to expire is not working.

The solution that works for me:

In ASP classic set cookie value to empty and cookie host to other domain. After doing this, this particular cookie will gone.

Response.Cookies("fbs_" & FACEBOOK_APP_ID) = ""

Response.Cookies("fbs_" & FACEBOOK_APP_ID).Domain = "anyotherdomain.com"

I believe if code in php, it will be simpler, Thanks to the cookie deletion idea given by this post:

Delete facebook session cookie from my application on users logout