Hi TS,

First of all, I'd like to confirm my understanding of your issue.
According to your description, I understand that you want to know why "F12"
doesn't go to definition when you use VS 2005.
If I misunderstood anything here, please don't hesitate to correct me.

"F12" is a shortcut used to go to definition in VS 2005 by default.
But we can change this setting in the "option" menu.

In general, I think the reason why F12 doesn't go to the definition is this
shortcut has been changed.
Please follow the steps below to check whether it has been changed.
1.Click "Tools" in your menu.
2.Select "Options"
3.In the "Options" dialog, please expand the "+" before "Environment"
4.Then select "Keyboard", you can find all shortcuts in VS 2005 from there.
5.Select the item "Edit.GoToDefinition".
Please check whether there is "F12(Global)" in "Shortcuts for selected
command:" textbox.
If not, you can change the setting by the "Press shortcut keys:" textbox
which is below the "Shortcuts for selected command:" textbox.

If anything is unclear, please don't hesitate to post in the newsgroup and
we will follow up.
Sincerely,
Wen Yuan