.
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- Data source and column names may include the following characters only:
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890_
*Note If you assigned a different data source separator, you can also use a "." in your data source and column names.
- Spaces are not allowed anywhere in a merge field.
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