Data exists, and then doesn't.

[J.Whitehead]

9185 chassis
9203 measuring three pressure transducers

9213 measuring 7 thermocouples

a set of scales using USB with a plugin to to read in FL

one calculated temp channel

running 2021 R1

After running a FL project and checking that data (which was all there), started the actual test, then vented everything (didn't do any part of the actual test yet). That data is fine.

Locked computer and went home, came in in the morning and started logging, Did the test (~2 hours long). Went to rename the file to the correct file name, it threw an error (unsure of file size, but it wasn't zero. yet). Tried to open file it said I couldn't. Closed prievew in diadem, went back to file location and file size was zero and can't move/delete that file.

Did not unplug anything in between tests.

This is not the first occurrence of this error. Has happened across multiple computers and multiple chassis etc. 

While performing the test, all data is showing fine in FL, there is nothing to indicate anything is wrong and happily chooches away just pretending to log.

[J.Whitehead]

As an interim fix I've manually stop/started the log to keep all test logs under an hour long. This seems to have stopped the data loss, but obviously not the cause of the original issue. Carrying out longer logs should not be an issue and are sometimes inevitable.

[J.Whitehead · Accepted solution]

TLDR: wetware issue, save directly to C:\

Turns out this was a me problem. (What I thought were) Local files are actually sync'd onto a network drive, which sometimes throws an error (unless you're aware of what to look for, it's very easy to ignore). The issue was when the error would occur during a file sync. The file name would be there, but as it was being copied to the network drive (who even knows when this might happen!) it would forget to link the files leaving it as an empty, broken file. The network files were able to be navigated to (albeit deeper into the system than one might like) and all was well. The better fix is to make sure your filesave path is directly onto your C:\, then obviously move to wherever tickles you.