lightroom 11.4 exporting file "the file could not be written" windows 10 pro

Lightroom has no prermission to export files to drive z:\ which is my ramdisk drive

rolled back to lightroom 11.3.1 and there is no problem

updated again to 11.4 and the problem still exist

all other programs like photoshop does not have this problem

again rolling back to 11.3.1 and again there is no problem 

hope it will be fixed next update...

ps. I did checked disk/folder - read/write permission is enabled