Usually at least a brief notice about any error is displayed in the Soa Gateway Log View.
If the Log View does not give any information, or the information presented is not sufficient to identify the problem, consult the Eclipse Error Log which is accessible from the Eclipse main menu bar via:
(this brings up a popup windows)
Click "Configuration Details"
Click "View Error Log"
Scroll to the bottom of the error log to view information about the last error having occurred.
Possible cause: please check if the JRE (Java Runtime Environment) in use it at least JRE 1.5, earlier levels may cause the behaviour described above !
When accessing the outside world from an intranet, it may be required to specify a HTTP proxy to Eclipse, this is done as follows:
Bring up the preferences dialog by selecting Window -> Preferences from the Eclipse main menu.
Select the Install/Update section, specify the Proxy settings as appropriate

Click OK to confirm the settings, Find and Install should now work as expected.