Here are the details of the error message I get when I call the SetDocumentAliasInfo method:
INSERT INTO CMS_DocumentAlias ([AliasNodeID], [AliasCulture], [AliasURLPath], [AliasExtensions], [AliasWildcardRule], [AliasPriority], [AliasGUID], [AliasLastModified], [AliasSiteID], [AliasActionMode])
VALUES (@AliasNodeID, @AliasCulture, @AliasURLPath, @AliasExtensions, @AliasWildcardRule, @AliasPriority, @AliasGUID, @AliasLastModified, @AliasSiteID, @AliasActionMode);
SELECT SCOPE_IDENTITY() AS [ID]
Caused exception:
The INSERT statement conflicted with the FOREIGN KEY constraint "FK_CMS_DocumentAlias_AliasSiteID_CMS_Site". The conflict occurred in database "Kentico-Kirksey", table "dbo.CMS_Site", column 'SiteID'.
The statement has been terminated.