Up to Promodag Reports version 7.7 only:

When  exporting reports to Excel format on Windows Server 2003 SP2 you get the following error message "error detected by export dll".  This a known Crystal Reports issue that is being investigated by Business Objects.

Workaround is to uninstall SP2, or to upgrade to Promodag Reports v. 7.8 as it contains an updated version of Crystal Reports runtime.