New Toad Version on same machine not able to detect Oracle Home, why and how can this be solved?

Toad for Oracle
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Oh, and I forgot to mention - 32 bit Toad can only use 32 bit Oracle clients. 64 bit Toad can only use 64 bit Oracle clients.

I have occasionally seen the registry get confused when it comes to Oracle clients. When that happens I remove all clients and start over, following these steps.