pssl
If you look further down the list of forums you will see Obselete releases.
I don't think you will get too much help there, although you can try.
I realise your predicament re hardware, BUT you are being very unwise to keep using a web connected server running an old and insecure version of sme. There have been no updates for sme 6.5 for probably 2 years or more, sme 7.x has been released for at least that length of time, and you would be wise to upgrade, even if it means a hardware upgrade.
Your problem could have many possible causes, including having been hacked. Log files are regularly rotated in sme, so I doubt that's your problem.
I don't think anyone here will want to diagnose sme6.5 problems, most of us have forgotten about the inner workings of sme6.5 anyway.
At a wild guess I'd suggest looking at memory usage using
top -i
and
htop
(I think htop was in sme6.5 but I can't remember, there's the problem for us).