Hi we have 1 WFE and 1APP server. we have aroud 10 We aplliaction.We configured search service application on APPLICATION server. Im facing some error while crawling for 2 web Aplliactions.Im getting  below error while crawling.I tried all possible ways.but no use.

Error:

An unrecognized HTTP response was received when attempting to crawl this item.Verify whether the item can be accessed using your browser.

Hi,

Make sure you have dns record for those web applications/sites and also if they access internet and you have proxy you will need to add the proxy on web.config

also check the root certificate

Check also AAM

check those links for similar issue

http://wellytonian.com/2012/04/sharepoint-search-crawl-errors-and-fixing-them/

http://www.infotext.com/help/sharepoint-could-not-estabilish-trust-relationship-for-the-ssltls-secure-channel-when-crawling-ssl-enabled-websites/

https://social.technet.microsoft.com/Forums/en-US/94e999e3-4128-4674-97dc-e46e71fe0f46/search-service-setup-behind-f5-an-unrecognized-http-response-was-received-when-attempting-to-crawl

http://serverfault.com/questions/92186/unrecognized-http-response-in-sharepoint-search-crawl