After contacting Sandisk about the problem with the new firmaware release, I was assured I would be emailed a fix within 24 hours. After not getting a response for a couple of days, this is the email I received.
I apologize for any inconveniences this issue may be causing you. But I wasn’t updated on firmware issue, apparently we not sending previous firmware anymore. The new firmware was made to be comparable with Windows “Play for sure” and from now on is going to be only MTP mode so with this said please describe in details what problems you having so we can better assist you to resolve this. Is it any arrow messages? What OS you using? What WMP version you have?
Thank you for contacting SanDisk Technical Support.
SanDisk Technical Support
Guess we are on our own. Many thanks to the person who provided info on restoring an archived copy of the old firmware. It works - Thanks Alice