My guess is that your .jpg file isn't really in .jpg format. Try another, known .jpg file and see if the same thing happens.
I just upgraded my pc (hd install) with the latest knoppix ..
I loaded up the gimp and then tried to open a jpg file that I d/l from the web... and I get this error:
" GIMP Message
Opening '/path to my file.......jpg...' failed:
Plug-in could not open image".
HELP !!!!!!!!!!!!
I used apt-get to remove the gimp, then I used it to re-download and install it but I get the same error both ways !
Any ideas on how to fix this?????
My guess is that your .jpg file isn't really in .jpg format. Try another, known .jpg file and see if the same thing happens.
Do file filename.jpg to see what it is.
I have verified that they are in fact jpg files.
I also tried with a few known jpg files and I get the same error.
What can this be ????
Did you use apt-get remove --purge to be sure configs are overwritten with new ones?

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