Solved Preview not working, please help

Preview is not working when I tried to write a new post in my forum. I tried all I read here but I don't know what more to do. I tried changing the SEO, disabling the plugins, updating all Kunena components, etc. but I was not lucky. Please, help! thanks!

Database collation check: The collation of your table fields are correct

Joomla! SEF: Enabled | Joomla! SEF rewrite: Enabled | FTP layer: Disabled |
htaccess: Exists | PHP environment: Max execution time: 300 seconds | Max execution memory: 512M | Max file upload: 64M

Kunena menu details:

Warning: Spoiler!

ID	Name	Menutype	Link	Path
237	Mi Perfil	footermenu	view=user	miperfil
212	Perfil	footermenu	view=user	perfil
135	Foro	footermenu	view=home&defaultmenu=134	foro-minerim
108	Foro	mainmenu	view=home&defaultmenu=240	foro-principal
207	Guías	mainmenu	view=category&catid=12	foro-principal/guias
213	Soporte	mainmenu	view=category&catid=8	soporte
270	Foro	kunenamenu	view=home&defaultmenu=272	foro
271	Categorías	kunenamenu	view=category&layout=list	foro/categorias
272	Mensajes Recientes	kunenamenu	view=topics&mode=replies	foro/recientes
273	Nuevo Tema	kunenamenu	view=topic&layout=create	foro/nuevo-tema
274	Sin Respuesta	kunenamenu	view=topics&mode=noreplies	foro/sin-respuestas
275	Mis Temas	kunenamenu	view=topics&layout=user&mode=default	foro/mis-temas
276	Perfil	kunenamenu	view=user	foro/perfil
277	Ayuda	kunenamenu	view=misc	foro/ayuda
278	Buscar	kunenamenu	view=search	foro/buscar

Joomla default template details : rt_oculus | author: RocketTheme, LLC | version: 1.0 | creationdate: Unknown

Kunena default template details : Blue Eagle | author: Kunena Team | version: 3.0.6 | creationdate: 2014-07-28

Kunena version detailed: Kunena 3.0.6 | 2014-07-28 [ Tala ]
| Kunena detailed configuration:

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Kunena config settings:
board_offline	0
enablerss	0
threads_per_page	20
messages_per_page	6
messages_per_page_search	15
showhistory	1
historylimit	6
shownew	1
disemoticons	0
template	blue_eagle
showannouncement	1
avataroncat	1
catimagepath	category_images
showchildcaticon	1
rtewidth	450
rteheight	300
enableforumjump	1
reportmsg	1
username	1
askemail	0
showemail	0
showuserstats	1
showkarma	0
useredit	1
useredittime	0
useredittimegrace	600
editmarkup	1
allowsubscriptions	1
subscriptionschecked	0
allowfavorites	1
maxsubject	50
maxsig	300
regonly	0
pubwrite	0
floodprotection	0
mailmod	0
mailadmin	0
captcha	0
mailfull	1
allowavatarupload	1
allowavatargallery	1
avatarquality	75
avatarsize	2048
imageheight	800
imagewidth	800
imagesize	150
filetypes	txt,rtf,pdf,zip,tar.gz,tgz,tar.bz2,rar,jpg,png,gif
filesize	120
showranking	1
rankimages	1
userlist_rows	30
userlist_online	1
userlist_avatar	1
userlist_name	1
userlist_posts	1
userlist_karma	0
userlist_email	0
userlist_joindate	1
userlist_lastvisitdate	1
userlist_userhits	1
latestcategory
showstats	1
showwhoisonline	1
showgenstats	1
showpopuserstats	1
popusercount	5
showpopsubjectstats	1
popsubjectcount	5
usernamechange	0
showspoilertag	1
showvideotag	0
showebaytag	0
trimlongurls	1
trimlongurlsfront	40
trimlongurlsback	20
autoembedyoutube	1
autoembedebay	0
ebaylanguagecode	es-es
sessiontimeout	1800
highlightcode	0
rss_type	topic
rss_timelimit	month
rss_limit	100
rss_included_categories
rss_excluded_categories
rss_specification	rss2.0
rss_allow_html	1
rss_author_format	name
rss_author_in_title	1
rss_word_count	0
rss_old_titles	1
rss_cache	900
defaultpage	recent
default_sort	asc
sef	1
showimgforguest	0
showfileforguest	0
pollnboptions	4
pollallowvoteone	1
pollenabled	1
poppollscount	5
showpoppollstats	1
polltimebtvotes	00:15:00
pollnbvotesbyuser	100
pollresultsuserslist	1
maxpersotext	50
ordering_system	mesid
post_dateformat	datetime_today
post_dateformat_hover	datetime
hide_ip	1
imagetypes	jpg,jpeg,gif,png
checkmimetypes	1
imagemimetypes	image/jpeg,image/jpg,image/gif,image/png
imagequality	50
thumbheight	32
thumbwidth	32
hideuserprofileinfo	put_empty
boxghostmessage	0
userdeletetmessage	0
latestcategory_in	1
topicicons	1
debug	0
catsautosubscribed	0
showbannedreason	0
version_check	0
showthankyou	1
showpopthankyoustats	1
popthankscount	5
mod_see_deleted	0
bbcode_img_secure	text
listcat_show_moderators	0
lightbox	1
show_list_time	720
show_session_type	0
show_session_starttime	0
userlist_allowed	1
userlist_count_users	1
enable_threaded_layouts	0
category_subscriptions	post
topic_subscriptions	every
pubprofile	0
thankyou_max	10
email_recipient_count	0
email_recipient_privacy	bcc
captcha_post_limit	0
keywords	0
userkeywords	0
image_upload	registered
file_upload	registered
topic_layout	flat
time_to_create_page	1
show_imgfiles_manage_profile	1
hold_newusers_posts	0
hold_guest_posts	0
attachment_limit	8
pickup_category	0
article_display	intro
send_emails	1
fallback_english	1
cache	0
cache_time	60
iptracking	1
rss_feedburner_url
autolink	1
access_component	0
statslink_allowed	0
superadmin_userlist	0

| Kunena integration settings:

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Kunena - AlphaUserPoints Enabled: activity=1 avatar=0 profile=0 activity_points_limit=0
Kunena - Community Builder Disabled
Kunena - Gravatar Disabled
Kunena - JomSocial Disabled
Kunena - Joomla Enabled: access=1 login=1
Kunena - Kunena Enabled: avatar=1 profile=1
Kunena - UddeIM Enabled: private=1

| Joomla! detailed language files installed:

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Joomla! languages installed:
es-ES	Spanish (español)
en-GB	English (United Kingdom)

Third-party components: AlphaUserPoints 1.9.10 | UddeIM 3.4

Third-party SEF components: None

Plugins: Search - Kunena Search 3.0.1 | Content - Kunena Discuss 3.0.1

Modules: Kunena Latest 3.0.1 | Kunena Stats 3.0.1 | Kunena Login 3.0.1 | Kunena Search 3.0.1

kemadiyo wrote: I tried all I read here ...

There are many topics here about "preview not working" . Which topics did you read?

The main reason why message preview doesn't work for some people is when there is a conflict with another Joomla extension that installed on your website.

Solved!!! , I found an strange code in the index.php located in the root, I remove it and working! This is the code I found:

<div style='text-indent:100%;white-space:nowrap;overflow:hidden;height:1px;'><h1>Main Menu</h1><ul style='list-style-type:none;'><li><a href=' www.plataformasteam.com '>Plataforma Steam

ForoGuate