问题
I attempt to upgrade a project group containing 200 projects from Delphi XE to Delphi XE2. Some of the IDE design components aren't install on Delphi XE2 IDE yet.
I encounter error when open some projects in Delphi XE2 IDE:
"Error Reading Form: Class TSynEdit not found. Ignore the error and continue?
Note: Ignoring the error may cause components to be deleted or property values
to be lost".
This is due to TSynEdit component is not install in the Delphi XE2 IDE.
I am in the stage of upgrading to estimate how much works I need to do. As I didn't open the form containing missing component, these messages keep prompt out whenever I open the project. It is very irritating.
Prior to Delphi XE2's IDE, these messages prompt out only when I open the form in IDE. It doesn't happen when I open project file in IDE. However, in Delphi XE2, these messages prompt out when I open project file IDE.
回答1:
As David suggested, now my comment as an answer.
XE2 internally opens all forms while upgrading the project. If you don't save the project it will be upgraded again the next time you open it.
So as you found by yourself: Save the project file, but don't save the forms as this would destroy the references to the non-existing components.
来源：https://stackoverflow.com/questions/7395965/delphi-xe2-encounter-error-reading-form-when-opening-a-project-in-ide