Re : Error Message Table 'tiki.tiki_articles' doesn't exist
tiki_articles is an old table... Are you sure you run tiki.sql at the install time or you upgraded correctly (db/tiki_1.xto1.Y.sql) for each upgrade step
Trick
1) save/dump you current database data.
2) create a new database
3) run db/tiki.sql (or the one specific for your db) to crate the table and some data
4) reload you data (ignoring the errors)