Help editing a thumbnail, please?

[Ardath Rekha]

I've been searching through the topics, but I don't see anywhere where this is specifically addressed...

I uploaded an image that, in full-size, is quite lovely, but the colors are muted enough that the thumbnail version is washed-out and hard to see.  I have a thumbnail version of this image with heightened contrasts, and I would like to swap it out for the thumbnail that the program generated, but it's not letting me do so.

I have tried using Dreamweaver, the site control panel, and FTPing in with IE, and in every single case, the file cannot be altered.  For whatever reason, despite owning the site, I am not authorized to delete the file, edit the file, change its permissions, or even upload a new file into the directory.  There don't seem to be any utilities that will allow me to edit or delete just the thumbnail; they all appear to be designed to edit or delete the whole image.

I'm uncertain as to whether this is a flaw in the program or a flaw with my webserver, because back in July they used something they call "phpsuexec" on the server and it appears to have really, badly messed with the numerical values associated with file permissions (they will not, however, admit that they could be responsible for any kind of problem... typical!) which has resulted in the 6 in 644 files frequently meaning read/write rather than read/write/execute as it ought to.  (Argh!)  At any rate, though, I can't actually alter the permissions of the files in the user/10001 folder anyway...

Does anyone know how I need to alter the folders, or the program settings -- or what I need to ask my webhosters to do -- so that I can swap out the one thumbnail for the other?  Have any of you dealt with this sort of strangeness?  And if so, how did you fix it?

[Joachim Müller]

Try CHMODing the files. If you can't do that, they probably aren't owned by you - as your webhost to CHOWN them for you.

Joachim