Solution
Only TDM and TDMS files support all the options listed in
"Overwrite options (if not wired)" in the Open Data Storage Express VI . If the DataPlugin you specify in the DataPlugin list is not a .tdms or .tdm file, LabVIEW uses the open (read only) option by default to open the data file. To write to the data file, you can wire a
create or
create or replace control to the
function (open:0) block diagram input and then use the Write Data Express VI to write data to the file.
If the write-protected error is shown, the DataPlugin is meant to be for reading only. In case the download link for said DataPlugin mistakenly shows a Read/Write direction, please submit feedback in the website to update the direction to the correct value, or
contact NI Support for confirmation.