QB Issue Resolution:
At this time, we can only customize the email message that sends Sales Forms. What you can do is create a default message that will appear on the actual Purchase Order. To do this:
Click the Gear Icon with your company name
Select Company Settings
Click Purchase Orders
Enter Default message on purchase orders
If you would like to request a way to customize email messages for purchase orders, I encourage you to send a message to our Engineers. Intuit loves hearing from customers and really appreciates your ideas! To leave feedback, go to the Gear > Feedback > Post your own idea.
Resolution for Issue 'Change Purchase Order Email Template.' available: Yes (Solved).
Source: Intuit Community forum.
Change Purchase Order Email Template.: 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 purchase order
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Error Recovery for purchase order [Canada]
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