Hi Vishal,


This has already been logged as a known issue, R&D teams are working on the same.

See the details below and check the link for updates. 


Login Call Using Tooling API Fails With UNKNOWN_EXCEPTION

API , Authentication

Last updated Yesterday ·Reference W-1895722 ·Reported By 7 users
IN REVIEW

Summary
Using the Tooling API WSDL to issue a login call via third-party application can result in an error similar to the following:

ERROR:- UNKNOWN_EXCEPTION: An unexpected error occurred. Please include this ErrorId if you contact support: 402343489-21430 (1318667741)

Repro
The following is a sample request and a response via the Tooling API.

REQUEST
=======
POST https://na10.salesforce.com/services/Soap/T/29.0

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:urn="urn:tooling.soap.sforce.com">
<soapenv:Header/>
<soapenv:Body>
<urn:login>
<urn:username>[**username**]</urn:username>
<urn:password>[**password**]</urn:password>
</urn:login>
</soapenv:Body>
</soapenv:Envelope>

RESPONSE
========
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:sf="urn:tooling.soap.sforce.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<soapenv:Body>
<soapenv:Fault>
<faultcode>sf:UNKNOWN_EXCEPTION</faultcode>
<faultstring>UNKNOWN_EXCEPTION: An unexpected error occurred. Please include this ErrorId if you contact support: 402343489-21430 (1318667741)</faultstring>
<detail>
<sf:UnexpectedErrorFault xsi:type="sf:UnexpectedErrorFault">
<sf:exceptionCode>UNKNOWN_EXCEPTION</sf:exceptionCode>
<sf:exceptionMessage>An unexpected error occurred. Please include this ErrorId if you contact support: 402343489-21430 (1318667741)</sf:exceptionMessage>
</sf:UnexpectedErrorFault>
</detail>
</soapenv:Fault>
</soapenv:Body>
</soapenv:Envelope>

Workaround
Use a different login method (oAuth / REST, Partner or Enterprise SOAP API) to get the Session ID.


https://success.salesforce.com/issues_view?id=a1p30000000T2GcAAK


Regards,
Ashish