The Dynamic WebDev site is not installed properly (invalid correspondence with the registry database). You need to reinstall the site, and/or check its configuration in the registry.
Reminder:
When installing a Dynamic WebDev site, a new entry is created in the registry.
A new entry is created in the key:
"HKEY_LOCAL_MACHINE\SOFTWARE\PCSOFT \WEBDEV\14\<ProjectName>".
The project's name and directory are specified.