NEEd HELP --> Error executing ImageMagick - Return value: 127

[erwan]

I tried to upload pics but I failed. the following message came out after I tried, "Error executing ImageMagick - Return value: 127".
What does that mean? I already tried to look it up on Help bur i did not find the solution of that kind of error. Please help here...
my site is already launched but there's no pic.
Please

[Nibbler]

Switch to GD2 in config.