I have a scheduler event that runs at midnight that's always worked on previous versions, but it will not create the file since upgrade to 3.23.

/queue simple print stats file stats

It works fine from the command line. I've tried executing a script instead, that contains the line, and it will not create the file either.

Any ideas?

Though I don't think it's your problem, you should have the equal sign:
You said you tried putting that in a script and then executing the script from the scheduler and it didn't work. Did you try running the script manually and did it work? I haven't had problems with the scheduler in 3.23 myself.

Sorry for the confusion. The scheduler executes , but the file does not show under files.
I created a script which also shows to execute, but the file does not show under files.
If I run the line from command line, the file appears under files.

I don't think the problem is with the scheduler, I think it's with the command itself:
/queue simple print stats file stats

Ver 3.23 doesn't seem to want to create the file stats.txt while running except from the command line.

Again, it works fine in the background in older versions.

A script with the command above works on my 3.23 router. Try creating a new script from scratch?

The problem was with policy.

I created from command line, and it added this and it created file okay:
policy=ftp,reboot,read,write,policy,test,winbox,password,sniff

I created scheduler event from the command line and it add this and didn't create file:
policy=read,write,test

I changed the scheduler policy to the one created in script, and the command creates the file just fine!

Thanks

yes, you need 'ftp' policy to work with files