Hi, Sylvain.
We are sorry for inconvenience - Cassini failing to load when some application path is incorrect is unintended and we'll investigate and fix it in the next release.
Cassini metabase file, CassiniMetabase.xml, is a regular XML file that you should have no trouble editing to correct the misspelled path. The file is located in "C:\Documents and Settings\All Users\Application Data\UltiDev\Cassini" folder on Windows XP and 2003. Saving metabase file after you are done editing it will automatically restart the service.
Best regards,
UltiDev Team.
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