If you want to create a letter for multiple records in one batch, you can do this by first filtering the grid for the desired records. Then above the grid, you'll select the Actions option. Click Print/Email Mail Merge and a dialog box will pop up. 

Select the desired mail merge template, whether it is to be shown as acknowledged, what delivery option you want to use, and if you want to archive the document. When finished, click the OK button to run the mail merge. Performing a Print/Email Mail Merge will create a letter for all records shown on the filtered grid.

If Print to PDF is selected, a new browser tab will open with all the letters shown as a single document with multiple pages (one for each letter generated). 

If Email link to PDF file is selected, another dialog window will open and allow you to customize the email message that will be sent to all the recipients. Each recipient will receive a personalized message and only their applicable letter.

If Print to Word is selected, the document will download into your Downloads folder as a multi-page Word document for editing and printing. Print to Word (Advanced) performs the same function, but works behind the scenes slightly differently to create the letter and works best for complicated mail merge letters with tables and charts. If the word document is not opening or downloading, check that pop-up blocker is not turned on for DonorView.

In Chrome, click the lock icon to unlock the pop-up blocker.

For very large mail merges, it may take some time to complete the action. If you have a large job, you will receive a message that the mail merge is in the queue and you will receive an email when it is ready to download. All the mail merges that go into the queue can be found in Workspace>Reports>Mail Merge Queue. Once the mail merge has been executed you can download it by clicking on View in the Link column.