Convert to Web Application error

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Hello,

VS2005 with SP1.
I succefully coverted my Web Site Project to Web Application project, but,
for an aspx class, the manuel (by right clic menu) 'Covert to Web
Application, gives the error.

'Could not parse the file app_support\myfile.aspx'
and no designer.cs file is created. It is working for all other aspx files
in this app_support folder ?

How to have it converted ?
Thanks for help.
CS


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