When you combine multiple emails into one PDF file, by default, the Email to PDF add-in will use the order or sequence in which the emails were selected in your Inbox. However, you can alter or re-order the sequence of the emails, using the the advanced mode options.
In your Outlook, select the emails that are to be combined into one single PDF file. And from the PDF toolbar, Click ‘Combine selected Emails into One PDF (Advanced…)‘ under Outlook > PDF Add-in toolbar > Save As PDF.
This will prompt you with the ‘Save As‘ dialog box. Specify a file name for the one PDF document, and also the folder where this PDF file will be saved.
Next, it will display the ‘Customize Sequence and Order‘ dialog box, with which, you can change or sort the order or sequence of the files in the way you want them to appear in the merged PDF file.
Use the up and down arrow buttons to change the sequence or, you can also drag and drop the emails using your mouse in the order you want. If you have some unwanted emails that you don’t want in the one PDF document, you can simply un-check them for exclusion. You can further overwrite the default watermark, security, page layout or orientation for this particular action only.
And this is how the one PDF document looks like in PDF reader software. You will notice that the add-in automatically adds bookmarks of the emails and attachments (if any). It also add page number for easy navigation and references.