Answer
Foxit PDF Editor Pro supports 'Action wizard' function that allows you to convert multiple PDF files to PDF/A.
If Foxit PDF Editor Pro is already installed, please follow below steps:
1. Run Foxit PDF Editor Pro and go to File->Action Wizard->Create New Action->Create, it will pop-up Create New Action window.
2. Click on the '+' icon of Convert->Compliance and choose Preflight, then click on the 'Add>'button to add it into right side panel.
3. Click on green '+' icon to add the files you wish to convert to PDF/A, then double click on the 'Specify Settings' button, it will pop-up Preflight: Action Wizard Setup window.
4. Under 'Run Preflight check using', please select 'PDF Standards ' and choose 'Convert to PDF/A-1b' and save it.
5.Click Save button on the Create New Action window, and save it with a name you need.
6. Go back to File->Action Wizard->Run Action to run the action you just created, and the files will be converted to PDF/A. (If you receive an error when trying to convert it, you may contact support by creating a support ticket from here so our support team can further assist.)
If Foxit PDF Editor Pro is not installed yet, you may go to our website https://www.foxit.com/pdf-editor/to download it for 14 days free trial.