Its not quite as simple as updating the references as each version of EPiServer also needs a specific database version, as there could be schema and stored procedure changes that the new code has a dependency on. (As an aside this is why I dislike the stored procedure model - keep your logic as code and use your database to persist only data)

You can use the EPiServer deployment center to help you perform the upgrade (remember this will be non-reversible so take backups before proceeding). One of the options allow you to upgrade a site to a more recent version. This process will run all of the upgrade scripts against your database too.

One thing that does look a little strange, is the version number reported from your database. I'm not sure exactly how these pan out, but 6004 > 5202 which makes me wonder whether your database version is actually too recent, and you're trying to downgrade somehow?

What version is your working copy, and what version are you attempting to work with?

Mark Thanks for the quick response.. :)

I'm use in 5.2.375.133.. but not change or upgrade my DB. my database is stored on a separate server, and my access is read-only.

I'm also think that version 6004 should support in 5202..

Anyway, where can I find the version of the reader epi database from there? The verion, It is stored in a table?

The best thing to do here is get a copy of the database and host it on your development machine. That way you can give yourself full access to upgrade / modify the database without any risk 

I'm still not entirely sure exactly what you are trying to do, but manually editing values in the database is risky! There is a stored procedure called sp_DatabaseVersion which will report the current database version. I've got the following sites running from these datbase versions

CMS 5 R2 5.2.375.7 is running from database version 5200

CMS 5 R2 SP2 5.2.375.236 is running from database version 5205

CMS 6 RTM 6.0.530.02 is running from database version 6004

So it looks as if you're trying to run CMS5 against a CMS6 database. This won't work as there have have been many changes between 5 and 6 in terms of how it stores its data (see the DynamicDataStore for example). They aren't backwards compatible, which is why there is an database upgrade process.