Mail Merge to lots of records - via .NET dataset

I have a dataset with one table, with loads of rows.

I have a two page document template, so can’t use tablestart & tableend, as they span sections.

I am using doc.MailMerge.Execute(DS.Tables(0).Rows(0)) but it never completes - it just hangs - currently have been waiting 20 minutes.

The same process using Word mail merge, to a CSV of the same data, completes instantly.

Any help please?

@Chrishaines Could you please attach your template, sample data and code that will allow us to reproduce the problem? We will check the issue and provide you more information.