1. Login to Online Check Writer and select Apps.
2. Click Zoho Books and click on Connect; then, you will be redirected to the Zoho Books login page.
3. Sign in to your Zoho Books account using the credentials.
4. Once connected, Import all the companies from Zoho Books by clicking the Import Companies button.
5. Click the View Bank Account Mapping button to import the bank accounts from Zoho Books and map them to the bank accounts in Online Check Writer.

To import checks

1. Go to Payments and select Import Checks.
2. Then, choose Zoho Books 
3. Choose the company and update Import Settings: select Time Span and Download Filter
4. Click Start Importing

Similarly, you can import bills and invoices from Zoho Books to Online Check Writer.

To import bills from Zoho Books, 

1. Go to Bill / To Pay
2. Click Import Bills and select Zoho Books  
3. Choose the company and update Import Settings: select Time Span and Download Filter
4. Click Start Importing

To import invoices from Zoho Books, 

1. Go to Invoice from Receivables bar
2. Click Import Invoices and select Zoho Books 
3. Choose the company and update Import Settings: select Time Span and Download Filter
4. Click Start Importing