HELP Website theme Not displayed For First time visits - Phpsession? Cookies?

[briggz5d]

Imagine visiting a website and what you first see is this:

  First visit no PHPsession ID stored.

UGLY! ALL WHITE!! and BADLY FORMATED TEXT!
Those are the words visitors use to describe my THEMELESS site for first visit and I bet 80% of visitor automatically CLOSE the ugly site without even clicking or scrolling down.

My website HAS a Theme - several themes including the default. But No theme displays for first time visitors until they are given a PHPsession ID.  (until they click on a link or refresh the page)

When they refresh the poorly loaded page the the real theme loads and shows like this:

        Ngbuzz refreshed

If your browser has no recent cookies of ngbuzz stored the theme doesn't load up.
I have tried several themes and I don't think that's the problem. it's not a file permission problem either.. I've tried talking to my host about it, No luck.
I searched smf support about PHPsession they say it's GOOD for smf.. So what I'm I missing.
This is costing me a lot of visitors - thought I could ignore it - Please HELP!!

[gamesmad]

It looks like the stylesheet isn't loading.  Do you have any modifications installed?  How long has this been happening for?  Did anything specific happen to cause this?

[mariusfv]

I had the same problem few time ago and was a host problem, I've contact my host and they tell me that for protection they blocked "shell_execute", something like that and they are comment the lines who: "shell_execute" and after everything works great.

[briggz5d]

Noticed this problem when I installed SMF 2.0 RC5 3 months ago - I did a large Upgrade to smf Gold 2.0 problem still persist.
The following modes are installed: and error logs are empty.
1.   New Manual Look
2.   FB & Twitter Sharer Mod
3.   Email Template Editor
4.   SimplePortal
5.   Remove Index.Php From URL
6.   PM to New Members   
7.   Add GooglePlus to Posts
8.   Online status on login
9.   Sitemap
10.   Caps_Lock_Detection_on_Login
11.   Aeva ~ Auto-Embed Video & Audio


@mariusfv
I have talked to my host about it but didn't get any reasonable response - I'll try again citing you case with shell_execute

[mariusfv]

Ok maybe this help you, this is the answer from my host:(this was happen on smf 2.0 fresh install):
The log from my host:

The situation was solved by comment lines what use:  php shell_exec, please check if now is ok!.

Jun 22 16:02:51 server-0106 suhosin[43983]: ALERT - function within blacklist called: shell_exec() (attacker '89.122.*.*', file '/home/my_username/public_html/Sources/Subs.php', line 3762)
Jun 22 16:03:20 server-0106 suhosin[45633]: ALERT - function within blacklist called: shell_exec() (attacker '89.122.*.*', file '/home/my_username/public_html/Sources/Subs.php', line 3762)

I hope this log will help you!

[briggz5d]

I contacted my host, he agrees that the "shell_execute" restriction is for my safety. He went on to disable it. But I see no change. Please keep the solutions coming.

[CapadY]

It look likes guest are using another theme then registered members where the path is wrong in the theme settings for the theme guests are using. So, check the theme settings.

[briggz5d]

progress so far:
My host worked on the "shell_execute" still didn't work - so I didn't a LARGE UPGRADE!!
After the Large upgrade which Uninstalls all Mods the problem was FIXED... I Cleared my browser cookies and refreshed the page, it loaded Just Fine with the Theme shown!!!

I installed Mods One By One and testing to see if the site still loaded properly, I found out a particular Mod called "Remove Index.Php From URL" brought back the page loading problem.

The "remove Index.php" mod removes the index.php extension from my URL.
From ngbuzz.com/index.php to ngbuzz.com
I'll report the problem at the mod creators support thread, and mark this as solved. Thanks for all your help.
I'm glad all my old links that don't have the index.php still work. I guess a index.php extension in a URL never Hurt nobody.