I'm not sure if I can help, but do you think you maybe getting back a digital state for a value instead of a Float32? Just food for thought.
By the way, thanks for the help with my connection issue. I read back through your earlier postings and I decided to downgrade my PI-SDK to 1.3.6.x from 1.3.8.x and now on the second call to the PI-OLEDB it doesn't hang. Thank you. Good luck with your issue.
I have a few things to try:
1) Why you're not passing anything to the function for the cn parameter?
2) Can you run the sql query (the last line in PI_ArchiveValue) separately and make sure it brings you back the expected archive value?
3) What's line 36 in PI_ArchiveValue?
4) Did you have a chance to check out Jimmy's suggestion?
By the way I created a new thread for your question as the old one was getting too long and the subject line was quite different than what we are discussing now