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Rules for Processing a Mail Form 
The overview below lists the exact rules for processing a mail form:
· Processing starts with the start page (the first page in the tree)
· Processing of a page is executed in the sequence of the assigned windows in the tree
· Processing a window means processing the output control of the window

These rules are relevant for letters, faxes, and PDF files only. Typically, an internet mail contains only one page.
Main window
Processing of the main window on a page is finished:
¡ If the main window is filled completely on the page and the output control has not yet been processed to the end or
¡ If the output control has been processed to the end or
¡ If a manual page break (see also Page Sequence and Number) is reached.
Subwindow
Processing of a subwindow is finished:
¡ If the subwindow is completely filled on the page or
¡ If the output control has been processed to the end.
After all windows of a page are processed, processing of the page is finished. A page break to a new page occurs as soon as the processing of a page is finished and:
¡ The output control of the main window has not yet been completely processed or
¡ A manual page break was executed in the output control of the main window or
¡ The page does not contain a main window.
The new page is the static next page. If a new page is called by a manual page break with page specification within the main window (dynamic next page), the system processes this page.
Processing of the form ends if the processing of a page is finished and:
¡ On this page the output control of the main window has been finished and no manual page break occurred at the end or
¡ On this page the output control of the main window has not been finished but there is no next page (neither static nor dynamic) or
¡ This page does not contain a main window and no static next page exists.

· The manual page break is executed only in the main window, which means that you can specify it only in the output control of the main window.
· For pages without a main window the system goes to the static next page after processing all windows. If there is no next page, processing stops.
· For particular applications it is possible to repeat the processing described above (one main window and several subwindows), so that actually a form with several main windows is created.