This may be an issue with our code but if we take a source PST and open it in Outlook we see the TO, CC and BCC (if they were in the message). If we then create a PST with ASPOSE, and open the new PST in Outlook, the TO, CC and BCC fields are blank. If you look at the PST in Kernel Outlook PST Viewer, the fields appear to be in the message. We tested with older versions of our source and found the change to 17.2 seems to be where the problem started. Running the code with pre 17.2 works fine and the new PST display in Outlook as expected.
I cannot say with certainty that something we change in our code did not cause this effect but our release 321 works and 322, which is 17.2 and a couple of seemingly unrelated changes in our code, fails.
Can you try and confirm this behavior in 17.2 and greater. We are currently on 17.4.