Delphi won't run: license information found, but not valid

If I try to run Delphi 7, I get this frightening message:

Register Delphi

Borland license information was found, but it is not valid for
Delphi.
You can not run Delphi without this information.

Click the 'Exit' button to exit Delphi.

[Exit]

Delphi was running fine this morning, but choked when I tried to load the project I'm working on.

• I reinstalled Delphi from the original disk: same message.
• I have just done a system restore from a few days ago: same message.

I don't know why.

According to the archives of Chillibear, here is what you do:

1. Delete your registry.slm file from the .borland directory within your user's folder within documents and settings (or just enter %userprofile%\.borland into your Explorer path box).
2. Run the D7Reg.exe file from within your Delphi 7 Bin directory.
3. Follow the registration steps (you don't have to register now).
4. All done. Open Delphi 7 as normal.