Getting error when upgrading from vb4 to vb5

[basslion]

When i click the upgrade button, i immediately get the following error

Unexpected Text:
<br /> <b>Fatal error</b>: Class 'vB_Db_Query_Stored_MYSQL' not found in <b>/home/admin888/public_html/vb5/core/vb/db/query.php</b> on line <b>336</b><br /> Any idea's what can be wrong here?

[Paul M]

Looks like missing files to me, re-upload all the files.

[basslion]

I will try that. Can you tell me why when i copy all the files from the vb5 upload folder to my server, why there are files that want to overwrite files with the same name and location? Is this normal?