I'm having this error now and then. It comes with a .rehash or when the bot wants to write an user file. It used to work without problems until yesterday.
I disabled all scripts, although its possbible that one of the scripts caused the start of the error. I still have enough space in my shell to read and make new files.
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Writing user file...
ERROR writing user file. (Operation not permitted)
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this was what I discovered when I opended the webmail of my shell . I never used it , and nobody knows that I have it so I didn't expected any mail.....
number of mails 7021
mailboxsize 5975536 bytes
wish me good luck in my quest for finding an admin of my shell
theres probably no more disk space on the device, or possibly in your directory.
how you can check it is...
try to make a new file and see if it will let you
pico newfile
type in it
then try to save it
also delete those mails, maybe they're from your crontab being messed up.