>>I have a textbox on a form, and MaxLength is set to default (0 = no limit), and all of the other properties like InputMask, Format, and such are default too (empty)
>>
>>However, when a user begins typing in that field, after about 20 characters or so, the textbox stop accepting characters.
>>
>>The textbox is bound to a string property on an object like this ControlSource = Thisfrorm.Object.cProperty
>>
>>What would make it become limited like this?
>
>How this cProperty is created and can you assign something like
>thisform.Object.cProperty = cast('' as M)
>to this property?

This value is loaded from an xml file when the object is built in the Init of the form.

Are you saying that any new input value into the textbox becomes limited to the initial length of the cProperty string?