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Go to the Salesforce login page and login as an Administrator.
Navigate to the Setup tab.
Under the PLATFORM TOOLS section, navigate to the Apps tab on the left menu.
Select the App Manager option.
In the same window, head to the top right corner and click on the New Connected App button to create a new application.
Fill in the required information in the boxes below.
Under the API (Enable OAuth Settings), check the Enable OAuth settings option.
View file name manual4 
Connected App Name | Enter any name of your choice. |
NOTE: The Connected App Name can only contain underscores and alphanumeric characters. It must be unique, begin with a letter, not include spaces, not end with an underscore, and not contain two consecutive underscores. | |
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API Name | Enter any name of your choice. By default, it just copies the Connected App Name. |
NOTE: The API Name can only contain underscores and alphanumeric characters. It must be unique, begin with a letter, not include spaces, not end with an underscore, and not contain two consecutive underscores. | |
Callback URL | Navigate to the plugin’s Connect To Salesforce tab and copy the Redirect URI as shown below  |
NOTE: Make sure that the URL must be present in “https://” format. | |
Contact Email | Enter any email of your choice. |
Available OAuth Scopes | Select Manage user data via APIs (api) and Perform requests on your behalf at any time (refresh_token, offline_access) options. |
Then, click on Save.
Now the user will be prompted with the confirmation page, click on Continue, and move to the next page.
Once this is done the user will be able to view the app they have configured, then click on the Manage Consumer Details button to get Consumer Key and Consumer Secret.
You might get a 2FA prompt depending on the login policies, enter the OTP or 2FA prompt if asked, to get Consumer Key and Consumer Secret which are necessary to enable a connection between Salesforce and WordPress.
Copy the Consumer Key and Consumer Secret and keep them easily accessible. These details will be required when setting up the plugin on Jira.
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Navigate to the Jira Salesforce Data Sync plugin.
Under the tab Connect To Salesforce, paste the Consumer Key and Consumer Secret from the Salesforce App.
Under the tab Connect To Salesforce, paste the Consumer Key and Consumer Secret from the Salesforce App.
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Click on Save Configuration.
Click on the Connect to Salesforce button. You will be prompted to enter your salesforce credentials, once entered, you will be asked for certain permissions, please click on Allow to connect to Salesforce.
Next Steps
Once your Jira Instance is connected with Salesforce, then you will need to Configure Field Mapping between Jira & Salesforce Fields.