I realise this is an old(ish) query, but I just resolved the issue a quicker way than formatting / redownloading as suggested above.
When I received the SanDisk device, the executable was named ‘Run_SanDiskSecureAccess_Win.exe’
I closed SDSA and renamed the executable ‘SanDiskSecureAccessV3_Win.exe’ - relaunched it and it updated fine.
It may be worth noting that mine complained it was still running while trying to update, however after clicking ‘Yes’ to retry a few times, it eventually updated and is running fine
Hope this helps anyone else with the same issue.