Wallet Setup Error — Could not open file …./wallet/ewallet.p12 to read data

Post Clone steps that need to be taken into account for R12 Payments to function properly.
After you clone an environment (…assuming that source system has the wallet setup for payment instructions) you need to do the following:

1. Copy the wallet files (*.p12 and *.sso) from source clone to the new cloned instance.  Note the directory the files are placed into.  In our case we put into $CUSTOM_TOP/wallet directory.
2. Rebuild the wallet file
3. Validate the wallet file has the proper permissions
4. Null the two columns: SYS_KEY_FILE_LOCATION and SYS_KEY_HASH in table IBY_SYS_SECURITY_OPTIONS
5. Log into Oracle EBS as Payments Setup Administrator.  Navigate to: Payments Setup –> Shared Setup –> System Security Options –> Wallet Setup.
6. You can now set the wallet in the UI with the ewallet.p12 file in the new path (note path from step 1 above).  The cwallet.sso is then generated in file system.

The next time you check the Wallet File setting in UI, it will be pointing to sso file.