This procedure will update your system from the older version of Veritas Dynamic Multpathing (DMP) to the current MPIO-based multipathing solution.
Note: This process will require some reboots.

1. Update Storport.sys to the latest version that is recommended by Microsoft. Storport.sys is heavily involved in multipathing and has received several important updates over the years. Please check with Microsoft site for their recommendations and latest version release.

2. Change the drivers for your HBAs to Storport drivers. For multipathing support, use a HBA storport driver version that is at least at the level that is listed on our HCL (a higher version is fine). Storport drivers are necessary for MPIO-based multipathing. You may want to check with HBAs vendor for their recommendations as well.
   
   

3.   Go down to a single path and Uninstall the existing multipathing:
   a. From Add/Remove Programs, find Storage Foundation for Windows - Server Components and select Change.
   b. In the setup wizard, there will be an option for Dynamic Multipathing (DMPASL). Remove the check next to any DMPASL components.
   c. Complete the wizard. (Reboot is needed).

4. Re-enable the second path to the storage (don't enable the second path until after multipathing is reinstalled). Enable and check the DMP DSM. Expand the list and choose the appointed array from the list. Complete the wizard. (Reboot is needed).

5. Re-enable the second path to the storage (don't enable the second path until after multipathing is reinstalled).