Support » Plugin: WP Photo Album Plus » Fatal error: Unknown: Cannot use output buffering in output buffering display ha

  • When I click a thumbnail in one of my albums, I get error: Fatal error: Unknown: Cannot use output buffering in output buffering display handlers in Unknown on line 0
    I have not accessed the albums for a while, so I have no idea what I have updated in between. Any suggestion on where to look?
    Best regards, Peter

    The page I need help with: [log in to see the link]

Viewing 13 replies - 1 through 13 (of 13 total)
  • Plugin Author Jacob N. Breetvelt

    (@opajaap)

    This is a link that works:
    https://www.pemoco.nl/zzssooi/foto-albums-11/?wppa-occur=1&wppa-cover=0&wppa-album=47&wppa-photo=3784
    I guess that it is a server limitation (e.g. memory_limit) that causes the crash.
    Can you check this setting? (use https://wordpress.org/plugins/php-info-wp/ )

    Plugin Author Jacob N. Breetvelt

    (@opajaap)

    BTW The widget Cache-control test is very faulty, it creats a <!DOCTYPE html><html> tag inside the page content:
    (fragment):

    Cache-control test</span></h4><div class="textwidget custom-html-widget">
    <!DOCTYPE html>
    <html>
    <head>
    <meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate" />
    <meta http-equiv="Pragma" content="no-cache" />
    <meta http-equiv="Expires" content="0" />
    </head>
    <img src='https://trigger.home.xs4all.nl/screenshot.jpeg' border="0" alt="Python weerstation"/>
    </html>

    Better fix that first…
    Also (tip) disable all kinds of caching while troubleshooting.

    Thread Starter deepcore2

    (@deepcore2)

    Hi,
    Removed both widgets, they were there just for testing the images. I have no caching plugins installed. The “caching test” was targeted on the windows internet cache loacally to display changed images.

    I looked at the PHP Info, but there is a load of info… What am I supposed to look for?

    Best regards, Peter

    Plugin Author Jacob N. Breetvelt

    (@opajaap)

    memory_limit

    Pls also verify (ask hosting provider) if php function ob_start() may be used (normally should!)

    Thread Starter deepcore2

    (@deepcore2)

    Hi,
    Asked for the function, wauting for an answer.
    Memory_limit local 256M master 128M

    Also I noticed not all albums have the same problem. Several albums just work, several others give different messages:
    Internal Server Error
    The server encountered an internal error or misconfiguration and was unable to complete your request.
    Please contact the server administrator to inform of the time the error occurred and of anything you might have done that may have caused the error.
    More information about this error may be available in the server error log.

    The error log shows messages like:
    [Mon Mar 23 15:32:18 2020] [error] [client 145.222.131.2] File does not exist: /home/vhosts/pemoco.nl/httpdocs/blog/wp-content/plugins/phpinfo.wp, referer: https://www.pemoco.nl/vakanties/athene-delphi-peloponnesos-griekenland-2013/?wppa-occur=1&wppa-cover=0&wppa-album=6
    [Mon Mar 23 15:32:19 2020] [error] [client 212.238.180.253] ModSecurity: Warning. Matched phrase “admin” at REQUEST_URI. [file “/usr/local/apache2/conf/modsecurity/contact.conf”] [line “4”] [hostname “www.pemoco.nl”] [uri “/blog/wp-admin/admin-ajax.php”] [unique_id “XnjIc38AAAEAAAjXKUUAAAAW”]

    I’m completely lost 🙁

    Plugin Author Jacob N. Breetvelt

    (@opajaap)

    phpinfo.wp does not show up anywhere in the wppa code.

    Just a few suggestions:
    Has someone put dangerous content in any album or photo description?
    Did you check all photos on virusses? jpg’s may contain malicious code…

    Try to isolate one album, try to find an offending photo as follows:
    first find an album with the issue, make a dummy album and copy all the photos to it (photo albums -> bulk), verify the proble exists and delete the photos one by one until the problem vanishes.

    OR, if you saved sources, ftp …/wp-content/uploads/wppa-source to your pc and scan it for virusses

    Thread Starter deepcore2

    (@deepcore2)

    Ok,
    – ob_start() can be used.
    – It’s not just a photo that fauils, but apparently all in an album.
    I get the feeling photo’s with geolocation cause the problem. The photos that work all have no geolocation info an no map is drawn… The photos I checked that fail do have geolocations. Could it be related to that? Can I set the albums NOT to draw the maps?

    Plugin Author Jacob N. Breetvelt

    (@opajaap)

    Make sure you do not have a gpx plugin, and set Table IX-K5: GPX Implementation to WPPA+ Embedded code.

    If it still does not work, switch it off entirely by setting it to — none —, and remove w#location from Table II-B15: Custom content

    You can not switch it off on an album basis.

    Thread Starter deepcore2

    (@deepcore2)

    All did not do the trick. I created a new album and started to import pictures from a failing album in parts. When I reached around 95 pictures, the crashes started. The album page itself displays correct, but when I click a picture to enlarge that, the crash occurs. I also noticed that it took increasingly more time to show the picture. So I guess it has something to do with indexing all images for the slideshow. So I tried to disable things at table IIB 2,3,7,10,14 trying to disable that, but without luck. The working album look sdifferent after toggling te option, but the failing album keeps failing and loading time of the selcted image still is long. What takes so long after clicking an image? Can that be disabled? At this point I feel my problem is just having to much pictures in an album.

    Thread Starter deepcore2

    (@deepcore2)

    Oh, and to add, it has nothing to do with coordinates and maps after all 🙁 In the smaller album, the maps display perfectly.

    Plugin Author Jacob N. Breetvelt

    (@opajaap)

    Maybe your browsercache is full? Tra tp clear it or try a different browser.

    Thread Starter deepcore2

    (@deepcore2)

    It’s confusing. Cleaned the chrome cache on one laptop. Album worked now. But, on other browsers also and on other laptop also ??? Then I installed WP5.4 and the WPPA update improving lazy-load on filmstrip and now problems are back again. Cleared caches again, without much luck. Although the album size seems to have shifted from around 95 to around 130 to start causing the problem.

    Is there a suggested image maximum per album in the first place or should that not matter?

    Anyway, I’ll let all internet caches cope with the updates, will cleanly start the laptops tomorrow and see where I get.

    Best regards, Peter

    Plugin Author Jacob N. Breetvelt

    (@opajaap)

    There is no theoretical maximum images per album. What matters is the ‘pagesize’, i.e. the max number of items in a single display.

    The usable ‘pagesize’ maximum is limited only by: browser cache size, server max memory, server max executiontime, speed/reliability of your internet connection.

    In case of problems with larger numbers, check the server error log for out of memory or execution time exceeded fatal errors.

Viewing 13 replies - 1 through 13 (of 13 total)
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