Resolves: bug 480869

Description:  Bug 480869 -  DS console: Can not delete DS instance
Fix Description: Create instance was broken, so no instances could be created for purposes of deletion.  Create instance was printing the following error:
Unable to find Pass Through Authentication Plug-In config entry.
This is because the search for this entry in AdminUtil.pm was getting an incorrect error message - something other than "Success"
This is because the FileConn->getErrorString() method was returning "0" instead of "Success".
Platforms tested: RHEL4

ldap/admin/src/scripts/FileConn.pm

@@ -213,7 +213,7 @@ sub getErrorCode {
 
 sub getErrorString {
     my $self = shift;
-    return ($self->{lastErrorCode} ? ldap_err2string($self->{lastErrorCode}) : LDAP_SUCCESS);
+    return ldap_err2string($self->{lastErrorCode});
 }
 
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