[RESOLVED] Possible session problem?

ByteTraveler

Just set-up a new domain with my hosting company, and to make a long story short....

I can create three "blank" pages... Nothing more than a session_start(), and links to each other. That's it.

As you can imagine, I can sit there all day clicking those events, and life is good.

As long as I don't use IE 6.

Firefox, Opera, and even the IE 7 beta behave exactly as expected.

But intermittantly, IE 6 will just display a "blank" page (view source shows nothing) with no error.

Hit "reload," and it's fine.

Now you might jump to the assumption that it's my client machine (not dealing with cookies, or what not).

But it happens with every single IE 6 visitor from around the country, regardless of ISP, or what have you. I've personally verified this on four of four machines with IE 6.

The hosting company only says, "If it works in the other browsers, it has to be your code, and we can't help you."

What code?

And here's the kicker.... I elimiate the session_start() from each page, and IE 6 is as happy as every other browser. Life is good.

Without any doubt in my mind, whatsoever, simply putting session_start in a page causes this intermittant IE 6 behavior.

Any ideas?

Thanks in advance!!

bradgrafelman

Do you have display_errors turned On, and error reporting set to E_ALL?

ByteTraveler

bradgrafelman wrote:
Do you have display_errors turned On, and error reporting set to E_ALL?

Yes - I should have mentioned that. No errors or warnings have appeared with error_reporting (E_ALL), and display_errors is "on" in php.ini (as confirmed when it reported some syntax issues elsewhere).

I should also add that my host has had some serious dns record issues with this domain, which they've said our now resolved, but this particular (session) problem remains.

But the thing that (seems to) defy all reasoning is, "why only IE 6?"

bradgrafelman

Do you still have this page online? If so, can you post a link to it?

ByteTraveler

bradgrafelman wrote:
Do you still have this page online? If so, can you post a link to it?

Yes, and I think I may be a step closer to solving this mystery.

First, I have found one or two people who do not have this problem, but it seems that most (about 7 out of ten now) do see what I'm seeing with IE 6.

But here's the "kicker"...

This problem ("Intermittent blank pages in IE 6 only") happen when:

1) session_start() begins the page, and...

2) The tags <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> and <meta http-equiv="content-language" content="en-us" /> are in the code!

I never thought to remove the tags (which I think was a Dreamweaver artifact when I cranked-out the test pages).

If I remove either (the meta tags or the session_start()) the problem vanishes?

It doesn't seem to be either-or with the tags - They have to both be there for session_start() to trigger this IE behavior.

But what's really crazy is that I've uploaded the same test scripts to my other domains, and there is no problem at all.

Can I be losing my mind? <smile>

It's like these two tags, together with session_start() just aren't making IE 6 happy only on this particular domain?

Here's the set of test scripts. All you can't see in "view source" is a <?php session_start(): ?> at the top of each page....

http://sandandsky.com/test/test1.php

Just rapidly click-around the links, back-and forth. Most people see a blank page (in IE 6 only) within 10-to-12 clicks, tops.

bradgrafelman

Yeah, actually, I got it in my first try.

Can you post the entire source of one of those pages? Wait... better yet, rename one (or a couple) of them to a .txt extension and actually attach the files to a message. I have an idea, but want to verify it by looking at the source.

EDIT: So, I tried running my IE6 browser through a TCP redirecting program which also lets me log everything that passes through the port, and here's what I found:

When IE6 shows a blank page, your server is sending a gzip compressed page. In otherwords, IE6 sees this:

264: Server to Client (739 bytes)
HTTP/1.1 200 OK
Date: Sun, 26 Feb 2006 02:32:16 GMT
Server: Apache/1.3.33 (Unix) DAV/1.0.3 mod_fastcgi/2.4.2 mod_gzip/1.3.26.1a PHP/4.4.2 mod_ssl/2.8.22 OpenSSL/0.9.7e
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Pragma: no-cache
X-Powered-By: PHP/4.4.2
Keep-Alive: timeout=10, max=99
Connection: Keep-Alive
Content-Type: text/html
Content-Encoding: gzip
Content-Length: 278

01E7  85 E8 C0 42 68 A2 49 55  62 31 EA 72 84 29 90 70  ...Bh.IUb1.r.).p
01F7  13 0E 42 DF 5E 6E 89 2C  6A BA 99 EB F7 FD F3 8F  ..B.^n.,j.......
0207  B8 F2 5E DC E0 D3 DF 41  42 79 06 FE DB FD FE D1  ..^....ABy......
0217  05 C6 11 DF 4D 17 D1 0B  3C F8 78 08 9E F6 A0 6B  ....M...<.x....k
0227  D7 70 A0 3A 0D 09 71 F7  CC 80 25 44 D5 2D 62 D7  .p.:..q...%D.-b.
0237  75 5A 67 6A 65 1D 63 F0  8A FD 98 A2 8F DA B2 E4  uZgje.c.........
0247  CD E4 68 11 45 CC D9 88  E9 91 3E CF 8A C6 3E 13  ..h.E.....>...>.
0257  A0 5B 96 35 7B 13 AB 64  34 4C 94 52 A6 1C 5F C6  .[.5{..d4L.R.._.
0267  0A 0C 81 F3 4E E0 72 99  2B 92 30 06 71 F5 DD A6  ....N.r.+.0.q...
0277  3F 36 0B CB 82 54 41 3C  93 45 DC 0E 0E 83 E5 C4  ?6...TA<.E......
0287  66 AA E0 6D C3 00 CF 69  EE A2 05 A7 6A AD 90 EA  f..m...i....j...
0297  09 C7 3E 77 10 26 B2 6E  14 D9 2D 1D F9 CD 9C F2  ..>w.&.n..-.....
02A7  55 46 A7 61 AA 1C 31 84  D5 EA 68 33 24 D5 D0 34  UF.a..1...h3$..4
02B7  E8 5A 95 54 6C AE AD 0B  94 43 E5 EA 3F D6 58 B1  .Z.Tl....C..?.X.
02C7  C6 05 D6 5C B1 E6 05 76  BB 62 B7 7F 2C 2E BD A7  ...\...v.b..,...
02D7  8F 39 9B 5F 5E 2B 2C DD  02 02 00 00              .9._^+,.....

Now, I don't know anything about gzip'ing webpages and whatnot, but it seems that IE6 should expect this, namely because it says that it can! How do I know? Note the "Accept-Encoding" field IE6 sends out:

264: Client to Server (525 bytes)
GET /test/test2.php HTTP/1.1
Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, application/x-gsarcade-launch, application/x-shockwave-flash, */*
Referer: http://localhost:12334/test/test1.php
Accept-Language: en-us
Accept-Encoding: gzip, deflate
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; .NET CLR 1.1.4322)
Host: sandandsky.com:80
Connection: Keep-Alive
Cookie: PHPSESSID=36d14a95d85ebf693bc480b956601d74

So, I bet if you disable gzip compression in the PHP directives, you'll be fine.

EDIT2: Did the same thing with Firefox. Firefox, like IE, also reports that it can handle gzip compression, but when your server sends the gzip-compressed page to Firefox, FF magically decompreses it without problem and displays it correctly.

So, why IE6 says it supports gzip compression but then dies when that type of content is sent, well... that's another M$ feature! 😉

ByteTraveler

bradgrafelman wrote:
Yeah, actually, I got it in my first try.

...

So, I bet if you disable gzip compression in the PHP directives, you'll be fine.

Thanks so much for all your help on this (and for confirming the "blank page," and thus, to a certain extent, my sanity).

The hosting company (Dreamhost) says this does not happen when they try it!?

So, I guess the next logical question is, how do I disable gzip when I don't have access to php.ini?

And strangely, with such "plain vanilla" code as this failing on IE, would it not be some indication that something's awry in the server configuration? I mean, I can't imagine a simpler page using session_start()?

Here's the source of the test files.... http://sandandsky.com/test/test3.txt

And here's a phpinfo(); dump from the server: http://sandandsky.com/phpinfo.php

Edit1: And still puzzling that the problem "vanishes" if I elimate the content/ecoding tags from the html?

Edit2: I also found that if I can get through all the pages several times without a "blank," I can flush the cache in IE, and the problems begin anew.

bradgrafelman

Try taking these two lines:

<meta http-equiv="content-language" content="en-us" />
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

out of all of your scripts, and send them in the actual HTTP headers instead, like so:

<?php
session_start();

header('Content-Language: en-us');
header('Content-Type: text/html; charset=utf-8');
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Page 3</title>
</head>
<body>
<p><a href="/test/test1.php">Page 1</a></p>
<p><a href="/test/test2.php">Page 2</a></p>
<p><a href="/test/test3.php">Page 3</a></p>
<p><a href="/test/test4.php">Page 4</a></p>
</body>
</html>

(do this for all pages)

ByteTraveler

Yes - That seems to have done it!

I guess the "why?" remains, given that it's only this domain (I'm too curious for my own good), but thank you so very much for your patience and all of your help!