After running fc5 x86-64 and having a few problems with plugins on firefox - have seen
the i386 suggestions to overcome this but have not tried it - I decided to upgrade to FC6 as distributed by Linux Format.

Now I get copious refusals to execute binaries. I was running mysql and on starting it, got message and line number for mysql_print_default. It will not start. Cannot run commands such as host, cannot stop running tasks such as bluetooth.

It seems it must be something to do with FC6 not recognising x64 architecture or running with a mix of old (ie fc5 x64 moodules) and new fc6 - architecture unknown.

Do I simply revert to fc5 x86_64? Certainly the Linux Format seems pretty dodgy - for instance, it refused to run graphics for a while, startx would not get it up. But after a night's rest, it booted up normally!

I'm not an expert so if you respond, please keep it simple. Saving all my user data and re-formatting to clear out FC6 completely would be a real pain but that does seem to be my best solution.

The first thing I would try would be to disable SELinux and see if that helps at all. In the GUI you should find a tab on thew security setting dialogue (the one you set firewall settings on)

have tried the selinux disablement to no effect - thanks for tip.

I now see on further investigation of hourly messages to root from cron
- starting Dec 25, that usr/sbin/mcelog generates "cannot execute binary" as well.

I give up, time stamps on these messages are for when I was away and machine
switched off! I don't believe there is a machine error but conceivably there might be.
I can use the system whatever else is going on except for mysql and I will just have to forego
that service until such time as inspiration or catastrophe on other uses hits!

I have just noticed that a large number of modules in /usr/sbin were updated
immediately prior to the messages to root about mcelog not executing.

They are mainly - but not exclusively - prefixed with an l in the listing being linked
to a file (not directory) called lvm. I guess, but am not sure that that is when I ran
the install of the linux format fc6 onto my fc5 x86-64. I am pretty convinced this caused
confusion in the lib64 lib libraries and I'm paying the consequences.