If you just want to read excel files quickly then the solution is: don't use the .NET interface. It's too slow.
Try this example code:
https://forums.ni.com/t5/Example-Code/Directly-read-Excel-xlsx-files-using-unzip-to-byte-stream-and/...
Troy - CLD
"If a hammer is the only tool you have, everything starts to look like a nail." ~ Maslow/Kaplan - Law of the instrument
