QB Issue Resolution:
Most QuickBooks accounts already have login access to the online service center by default. If you have one of the accounts below, sign in to your online service center using the email address you provided at sign-up.
QuickBooks Pro, Premier, Enterprise, MAC and Online version
Mobile Payments (via GoPayment)
Hosted PayPage/Intuit Web Payment
Intuit Online Terminal
For other payments accounts an online service center (merchantcenter.intuit.com) username must be created manually using the email on the account.
Merchant service for terminals
Go to the Intuit Small Business web site. Below the sign-in fields, under the section labeled Don’t have an login yet? Click the click here link.
NOTE: If a message appears indicating the username already exists go to Step 4 below. If that username is associated with another merchant account, you will need to contact us to change email for the new merchant account to a new unique version.
Complete the required fields and then click Submit.
Email Address – Make sure to use the email address associated with your merchant account.
Password/Retype Password – Enter a password that includes at least 1 upper case letter, 1 lower case letter and a number. Must be between 6 and 32 characters in length with no spaces.
Company Name – Enter the name of the company. There is a 32 character limit in this field.
You will receive a message stating Registration Successful.
Go to the online service center and log in with the user information that you previously created and then click Sign In.
You will be forwarded to the Add a Merchant Account to the Merchant Service Center page. Click on I need a confirmation code.
Enter your merchant number and then click Submit.
A pop-up window appears indicating that an email is being sent with a confirmation number. Click OK, leave the window open and check your email.
Note: The email may take up to a couple hours to arrive.
Copy the confirmation number from the email you received.
Return to the Add a Merchant Account to the Merchant Service Center page and click I have a confirmation code.
Enter your merchant number again. Paste the confirmation code from the email in the appropriate field, enter the security text, and then click Submit.
You are then directed to your online service center. From now on, you can use the username and password you created to sign in to http://merchantcenter.intuit.com.
NOTE: To combine payments accounts to view under one username see Combine payments accounts so they can be viewed under one login in the online service center
Resolution for Issue 'Create a username or user ID for the online service center.' available: Yes (Solved).
Source: Intuit Community forum.
Create a username or user ID for the online service center.: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for Online service center
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Error Recovery for Online service center [Canada]
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