Have you done any experomenting yet?

No, sorry. But I did find this in MSDN if that is any help:

Knowledge Base

WD: Error Messages When You Try to Connect to a Mail Merge Data Source by Using the Mail Merge WizardPSS ID Number: 318532

Article Last Modified on 10/7/2003


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The information in this article applies to:


Microsoft Office Word 2003
Microsoft Word 2002
Microsoft Word 2000

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This article was previously published under Q318532
SYMPTOMS

When you try to connect to a data source while you create a Mail Merge document, you may experience one of the following symptoms.

After you select your data source in step 2 of the Mail Merge Wizard, nothing happens.
When you use the Mail Merge Wizard, you receive the following error message:

Word was unable to open the data source.
When you use the Mail Merge Wizard, and you connect by using MS Query, you receive the following error message:

ODBC Microsoft Access Driver Login Failed

Could not find file file name.
When you use Microsoft Visual Basic for Applications code to perform a mail merge with external data, you may receive the following error message:

Run-time error '9105'
String longer than 255 characters

Additionally, when you view the connection string in the Immediate window after you pause your code, only the first 255 characters of the string are displayed.
CAUSE
This problem occurs because Word cannot create a connection string that is longer than 255 characters.
STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.
Keywords: kbnofix kbbug KB318532
Technology: kbWord2000 kbWord2000Search kbWord2002 kbWord2002Search kbWord2003 kbWord2003Search kbWordSearch kbZNotKeyword2