phpthumb error on uploading image

Hello

i meant the TOP level (Root) joomla folder

in case it helps someone: i had a similar problem (only when hosted at strato.de), solved mine like this:
1) open /components/com_flexicontent/librairies/phpthumb/phpThumb.config_OVERRIDE.php
2) temporarily set $ PHPTHUMB_CONFIG [ ' disable_debug ' ] = false to see the debug result by removing line comment.
3) find ~'document_root', copy it's value.
3 a) in my case, the joomla-subfolder was missing here
4) set $ PHPTHUMB_CONFIG [ ' disable_debug ' ] back to true by re-adding line comment "//".
5) near "$ PHPTHUMB_CONFIG [ ' document_root ' ] = " set the correct path: in my case: the previously copied website-path ."/".<joomla_root_folder>
6) voilá: thumbnail got generated without error.

ps: remove the spaces in the $ PHPTHUMB_CONFIG - vars. I had to put them in in order to prevent this forum-editor to alter my text.

Thanks for helping !!

i forgot to suggest this

@hervemlam
please find (correct) real path and test setting it (see instuctions in previous post)

Hello,

Sorry, I forgot to mention I don't have the problem anymore:

Firstly, I encounter the problem when hoste by biz.nf, and it seems I solved it by removing 2 corrections I made before to fit my site when hosted by Free! (1 on controller.php, and the other one to disable lock tables, if anybody's interested).

Secondly, my site's being hosted by RaidGHost now since 3 months, and I never noticed this problem.

Good night.
HervE