The trouble with Protected Mode in Selenium 2 for setting cookies...

If you try to set cookies using the WebDriver API through Selenium 2, you may find that Internet Explorer fails to even set the cookie. The issue has been reported here:

http://code.google.com/p/selenium/issues/detail?id=1227&q=cookie&colspec=ID%20Stars%20Type%20Status%20Priority%20Milestone%20Owner%20Summary#makechanges

Selenium has a bunch of test suites to verify the behavior so it seemed strange that there would be an issue. Examining the IEDriver code too shows that the AddCookieCommandHandler is very similar to behavior of DeleteAllCookiesHandler and other IE command handlers, so I didn't really find an issue. Nor did the AddCookie() method in DocumentHost.cpp handles the dispatching of adding cookies.

If we do:

>>> driver = webdriver.Remote(desired_capabilities=current_env,
                                        command_executor="http://localhost:4444/wd/hb")
>>> driver.execute_script("document.cookie='a=1';")
>>> driver.get_cookies()
[{u'name': u'a', u'value': u'1', u'path': u'/', u'hCode': 97, u'class': u'org.openqa.selenium.Cookie', u'secure': False}, {u'name': u'sessionid', u'value': u'e1257265399f35b5c7ae4cf630581c90', u'path': u'/', u'hCode': 607797809, u'class': u'org.openqa.selenium.Cookie', u'secure': False}]
>>> driver.delete_cookie('a')
>>> driver.get_cookies()
[{u'name': u'sessionid', u'value': u'e1257265399f35b5c7ae4cf630581c90', u'path': u'/', u'hCode': 607797809, u'class': u'org.openqa.selenium.Cookie', u'secure': False}]
>>> driver.add_cookie({'name' : 'a' , 'value' : '2', 'secure' : False})
(Pdb) driver.get_cookies()
[{u'name': u'sessionid', u'value': u'e1257265399f35b5c7ae4cf630581c90', u'path': u'/', u'hCode': 607797809, u'class': u'org.openqa.selenium.Cookie', u'secure': False}]

Both delete commands will work successfully. But doing an add_cookie() fails to work if IE7/IE8 are in Protected mode in Selenium 2.5.0, even though Internet Explorer/IEDriver does not report any error. However, I was able to get cookies to be set once I disabled Protected mode.

Since Selenium 2.5.0 requires all Protected Mode settings to be consistent, you have to go into your Internet Options and uncheck the Protected Mode for every single zone (i.e. click through the icons for Internet, Local Internet, Trusted sites, Restricted sites). Then cookies can be correctly set.

It appears that IE7 and IE8 have this issue. IE9 may not have this problem. I was not able to get cookies set in either Protected/non-Protected mode using Selenium v2.0.0b3 though so you may still need to upgrade to Selenium 2 beyond this version to get cookie support working in IE7/IE8.