WinSCP process terminated with exit code 1.

This problem does not occur every time, restarting the application still exists, and need to restart the computer to solve it

And does the folder C:\Users\Administrator\AppData\Local\Temp\1 exist?

The directory C:\Users\Administrator\AppData\Local\Temp\1 does not exist.
After manually creating the directory, the program runs successfully.
Why WinSCP can not create folder automatically sometimes?
Thanks!

WinSCP does not create the directory. Why would it? It creates the log either implicitly in the the Windows temporary folder or to folder you tell it using Session.XmlLogPath.
If first case, the temporary folder must exists. If it does not, your machine is misconfigured and you must have lot of other problems. Or you told WinSCP explicitly to uses a non-existing path.

I had the same issue; the problem was not in my user profile. My script would run fine sometimes and other times it would error out with the same error message in this topic. What I found out is that when it failed, I had an Edge window open (to this site), which happens to be also creating and locking some files in the same TMP directory, if I close my Edge browser window, the locked files created in the TMP folder by that window are deleted, and when I run the script, it works just fine. I also tried deleting the TMP folder and making sure I close all browser windows and then run the script, it works, it even recreates the TMP folder.