Your Salesforce security token should have been emailed to you when you set up your Salesforce account or the last time you reset your password. If you are unable to find this email, you will need to reset the token. How to reset it will differ depending on whether or not your administrator has updated your Salesforce to the new layout released in Summer '13.
If you do not see the option to reset your token, you may be using IP Login Restrictions in Salesforce. Because this restriction disables the use of security tokens, organizations with this in place will not be able to sync with HubSpot. To check this setting in Salesforce, navigate to Setup > Security Controls > Network Access. If you have further questions about IP Login Restrictions, please contact Salesforce support for further assistance.
Note: Resetting your security token will break any existing integrations with your salesforce.com account. You will need to update your security token in any other integrations that requires it
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