the first item in the change list addresses your issue. Good timing: same day fix

Well, maybe not such good timing, as the data has been lost already. :-(

But the really great news is that moving forward @User-Name can continue working just like always, without a concern that he should have an independent backup strategy in place for his valuable data. Thank goodness. :-)

Also, if I’ve understood correctly, another fix is in the works that will be in the next version of Notepad++ (v8.1.6 most likely)

In fact, per this announcement , the first item in the change list addresses your issue. Good timing: same day fix. ;-)

FYI, this forum is made up of fellow users of Notepad++; it isn’t the bug/feature request location, so we cannot “fix this ASAP”.

Further, you don’t say what version of Notepad++ you were using, so maybe it’s already been fixed in a newer version – there have been a lot of improvements to the NUL file issue in the 4 years since the post you were replying to, and the number of NULL-file reports has dropped significantly. Also, if I’ve understood correctly, another fix is in the works that will be in the next version of Notepad++ (v8.1.6 most likely), so it’s about to get even better.

If it really was a saved file, and not a file with unsaved changes, and if it really was your “most important file”, then you were hopefully making use of revision control software and/or backup software; if you were, then you can use that to recover. Or if you have Microsoft Windows’ PreviousVerions/VersionHistory feature enabled, you might be able to use Windows Explorer to right click on the file, and choose Properties > Previous Versions. If you were not using backup software and that Windows feature isn’t active for you, there is software available from other sources (not from Notepad++) that can recover lost files – Recuva is one that’s often quoted in this forum – so that might help you recover the corrupted file; after trying recovery software, whether you are successful or not in getting your file back, I highly recommend that you learn the lesson from this experience, and start using backup software and/or version control software to make sure this is never a problem for you again.

For the future, Notepad++ has some different built-in or plugin-based features for taking a more active role in your backup procedure; you will want to read the FAQ: Periodic Backup vs. AutoSave Plugin for more on getting the most out of your Notepad++-based backup experience.

In the end, remember: “Only YOU can prevent Data Loss” (to misquote Smokey the Bear)

I lost one of my most important saved file. It was just opened in Notepad++, and after crash…all contents gone.

This is the biggest blunder.

Fix this ASAP and also tell me how to recover the file now.