The primary Gmail account defines the main YouTube page/account, calendar entries, and other features or services you use. To change your primary Gmail account, you will need to sign out of all existing accounts and log back in through your browser which will later save your account preferences. After that, you can add other accounts to the newly assigned main account.
Step
Part 1 of 2: Changing Primary Gmail Account
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Step 1. Visit your Gmail account inbox
Make sure this account is the primary account that is currently active before you proceed to the next step.
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Step 2. Click the profile photo
You can see this photo in the upper-right corner of the inbox page.
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Step 3. Click "Sign out" on the drop-down menu
You will be logged out of your main Gmail account and all the accounts associated with that primary account.
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Step 4. Click the account you want to use as the primary account
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Step 5. Enter the account password
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Step 6. Click "Sign in"
You will now be logged into the account you want to set as your primary Gmail account. From here, you can add other accounts to the main account.
Part 2 of 2: Adding an Account
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Step 1. Click on your profile photo
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Step 2. Click "Add Account" on the drop-down menu
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Step 3. Click the name of the account you want to add
Alternatively, click the " Add account " link at the bottom of the page to add a new account.
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Step 4. Type in the additional account password
If you added an account with previously disconnected connections, you'll also need to enter the account's email address.
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Step 5. Click "Sign in" when finished
Your second account can now be accessed and linked to the new main account.