asp.net does not revolve around files like old scripting languages did... <BR><BR>you are working with Objects. you may want to step back and look at the problem again... you can probably be much more efficient creating a user control, a .ascx file, and calling it from the two of your aspx pages.
The exact same method still works:<BR><BR><!-- #include file --><BR><BR>However, this is more for backwards-compatibility. What you really want to do is use user controls. User controls were originally called pagelets to give the idea that they were like ss includes. If you used ss includes before, and you know how to make a code-behind file, you should have no problem making user controls. They offer everything that includes do AND fit tightly in OO asp.net. Most .aspx pages are using at least a header, footer and navigation user control. They can do a lot more, however. For instance, I built a user control with basic search panel, advanced search panel and search results panel. All the user interface and OO code is contained in the .ascx file and .dll assembly!