回复：回复：回复：谁是PDF(ADOBE)专家阿？我发包子求教个问题。

Found from somewhere else:

"You may have discovered that some PDF forms on other sites can be saved with data intact, such as IRS forms. Adobe Reader does have a "hidden" ability to save data on forms, and this feature can be activated when the form is created. However, there is a very steep licensing fee that must be paid by the creator of the form in order to activate this feature, and that fee must be paid for each individual form, and paid again each time the form is changed. "

Your copy of Adobe Acrobat may not have this features activated.