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This message will be returned for any ip Unauthorized IP address that attempts a remote connection using the JavaScript API, SOAP API, or one of the legacy XML APIs. This is a security measure to lessen the chance of someone stealing credentials and harming a merchant's account.
Solution
Login to https://secure.ultracart.com and navigate to:
| Panel |
|---|
Home → Configuration → Users |
Navigate from the Main Menu, first clicking Configuration, Then clicking Users
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Click :
From the Users and Permissions section, click the edit button for the login that will be used to connect remotely.
Scroll down the page a little, and in the left column will be Permissions.
To the right of API Access is a link [IP Addresses]. 
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