Is there any limit for the number of control (text boxes) allowed on a form? I have a form with nearly 1000 text boxes and want to be sure InfoPath will allow this many. Thanks
As far as I know the limit is based on the SharePoint Column limits that is 276 for Single line of text
You can check the details for the limits here
If your form is a regular InfoPath template (not a SharePoint list form) you will only be limited in the amount of fields you can promote to a library (if the form is published to a SharePoint library) - to my knowledge, there is no constraint on the number of fields you can have in a form.
That said, a data source with 1,000 fields usually has potential for normalization - I often see data sources with lots of fields that should be using repeating structures instead - just a thought.