server is already active for display 0

[#piritrom]

`m running LinuxMint 4.0 as my only OS [it is simple and it works out of the box, I´m newbie, is been hard but the choice is done] in a brand new machine, ICDuo2 T7250 2GB,nVidia GForce 8 series,PCI-E Intel,250GB SATA,...network wireless its fine so here its the base system.
I`ll be using the machine to edit video so next its dyne:bolic but here it comes the newbie trouble:
Fatal server error:
Server is already active for display 0
If this server is no longer running, remove /tmp/.X0-lock
and start again.
well this happens what ever the distro i`m running as a base system and whatever the liveCD try to runnig dyne:bolic, ubuntu LTS, debiam,....So is it a default setting the trouble? what should i do?
found this: http://wiki.x.org/wiki/FAQErrorMessages#head-00b7778
but i`m afraid to do it becouse the comand rm-rf its involve and we`d been advise NEVER DO IT by LinuxMint developers.

[Husse]

sudo rm -rf /tmp/.X0-lock

is OK

rm-rf its involve and we`d been advise NEVER DO IT by LinuxMint developers.

Something like that - never to do it unless you know what you are doing or are being told so by a reputable source. This rm-rf empties tmp
I get this now and then when I've changed to pure command line (not rebooted) and forget that and then use " startx "