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1. Backup your existing data folder
2. Copy all the folders from the extracted latest version download data folder   into your existing  data Upgrade folder. This will replace existing Crcdata, Hivedata, Metadata, PMdata folders. Example:  Downloads\i2b2core-upgrade-1713\i2b2\data to C:\opt\edu.harvard.i2b2.data\Release_1-7\Upgrade\.
3. Copy the db.properties files from your back up into the respective locations (namely Crcdata, Hivedata, Metadata, PMdata )
4. Open the command prompt and navigate  to each cell folder and run the following upgrade ant commands on your i2b2 database instance, where {db} can  be Oracle, sqlserver or postgresql.
   Alternative to above Step, you can run individual SQL scripts on your db instance in place of  ant commands.
5. IndatafolderIn datafolder\Release_1-7\Upgrade\  run the ant commands under each individual cell folder as below

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Finally,  upgrade your db instance ( if Postgres) with stored procedures. Details are here

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