Go Offline with Microsoft Dynamics CRM 4.0

At a customer, one of their clients couldn't go offline.
After some digging I discovered that the Local Data Group Setup was taking all Accounts. The clients that worked going offline only had a few accounts and none of these accounts had any error. After the Local Data Group on these records were set to all accounts they failed too.
So as the error said that the lenght of customeraddress1 was too long, I looked at the field in both the local SQL Express on the client and on the crm's sql database. On entity Address attribute Address1 was 50 on client and 150 on server SQL.
So i changed the lenght on the client. Look below to see how i found my way through the lenght of attributes.
Still didn't work. Now the error was more generel. Customeraddress couldn't be imported.
I forgot to check for additional attributes that mismatched the lenght in both crm server and client.
Changed postbox and everything worked.

Now, how can this error occur?

The installation on client was a Microsoft Dynamics CRM 4.0 for Outlook with offline capability.
I installed it from www.microsoft.com/downloads with the version where UR7 is included. After successful installation i installed UR9 on top of that, because that was on the server.

I would expect both database schemas to be in sync when the CRM team released new versions to both servers and clients (and srs and data migration manager and email router). But apparently the test before release does not cover all the possible combinations of clients, ur's and servers. Hope that will be better in the future.

To check the schemas for the server and client databases follow the guides from this blog: http://blogs.msdn.com/jannemattila/archive/2008/02/13/comparing-two-databases-schema-and-or-data.aspx