Did ClientLogin API shut down?

Question

We have managed SNS service for Samsung mobile(feature phone, camera).

We are facging issues regarding ClientLogin API. When we request ClientLogin and then we receive response: 404 Error.

This API was only a few hours before the operation.

We can't upgrade to OAuth2, because of the device firmware update is not possible.

Is there remains to be still available?

The formats of request and response are as follows

####################### REQUEST #######################
POST /accounts/ClientLogin HTTP/1.1
Content-Type: application/x-www-form-urlencoded
Content-Length: 87
Host: www.google.com
Content-Type: application/x-www-form-urlencoded
Proxy-Connection: Close
Connection: Close

Email=&Passwd=&service=lh2&source=SamsungMobile+SNS+Gateway

####################### RESPONSE #######################
HTTP/1.1 404 Not FoundContent-Type:text/plain
X-Frame-Options:DENY
Cache-control:no-cache, no-store
Pragma:no-cache
Expires:Mon, 01-Jan-1990 00:00:00 GMT
Date:Wed, 27 May 2015 00:09:55 GMT
X-Content-Type-Options:nosniff
X-XSS-Protection:1; mode=block
Content-Length:65
Server:GSE
Alternate-Protocol:443:quic,p=1
Connection:close

https://developers.google.com/accounts/docs/AuthForInstalledApps

Answer 1

ClientLogin has been shut down.

Answer 2

As you can see in the link you posted Google Identity Platform

Important: ClientLogin has been officially deprecated as of April 20, 2012 and is no longer available as per our deprecation policy. We encourage you to migrate to OAuth 2.0 as soon as possible.

ClientLogin is a deprecated authentication protocol and is being turned down on April 20, 2015. At that time, ClientLogin requests will no longer be answered. If you have existing applications that use ClientLogin, we encourage you to migrate to OAuth. The ClientLogin support in this library will be removed in the next major release.

Its not going to work anymore you will have to upgrade or retire the application.