WD2000: Error Message: Word Could Not Open <File Name.doc> as a Data or Header Source Because It Is the Active Mail Merge Main Document

When you set up a mail merge in Word, you may receive the following error message: where file name.doc is the name of the document you are attempting to use as the data source.

The file that you are attempting to attach as a data (header) source has been previously set as a main document in Word.

Make sure the document you want to use as the data source is actually the data source and not a mail merge main document. If it is actually the data source, you can reset it as the data source by following these steps:

1. Close all documents currently open in Word.
2. Open the data file you want to use in your mail merge.
3. On the Tools menu, click Mail Merge.
4. In the Mail Merge Helper, click Create and then click Restore to Normal Word Document.
5. When you receive the following message, click Yes:
   By restoring file name.doc to a normal Word document, the text of the document will not change. However, file name.doc will no longer be a mail merge main document. Do you want to continue?
6. In the Mail Merge Helper, click Close.
7. On the File menu, click Save, and then close the file.
8. Perform your mail merge again.