How to Resolve ‘Invalid Login Attempt’ for NetSuite Sandbox TBA Web Services?

The 'Invalid Login Attempt' error, particularly when accompanied by an 'Invalid Signature' detail in the Login Audit Trail, often indicates an incorrect account ID (realm) format for sandbox connections.When connecting to a NetSuite sandbox account via web services, the account ID (realm) must adhere to a specific, case-sensitive format:

{accountId}_SB#

For example: 1234567_SB1

The tokenPassport XML structure should reflect this format, as shown below:

xml
<tokenPassport xsi:type="platformCore:TokenPassport">
            <account xsi:type="xsd:string">1234567_SB1</account>
            <consumerKey xsi:type="xsd:string">****************************************************************</consumerKey>
            <token xsi:type="xsd:string">****************************************************************</token>
            <nonce xsi:type="xsd:string">MTU1ODcxNDQ3Mw</nonce>
            <timestamp xsi:type="xsd:long">1558714473</timestamp>
            <signature xsi:type="platformCore:TokenPassportSignature" algorithm="HMAC_SHA256">********************************************</signature>
</tokenPassport>

It is important to note that the account ID returned by runtime.accountId and the account ID found in the URL use a different format: {accountId}-sb#.