Unrecoverable error: syntaxerror
 in token
Operand stack:
    --nostringval--
  --nostringval--
  [
  IconPosition::Bureau20012004.jpg
  --nostringval--

Sorry for posting, I found the source. It was the environment variable $GS_LIB pointing to its old destination which isn't valid anymore.

INITIALIZATION FILES
 
 When looking for the initialization files "gs_*.ps", the files related to fonts, or the file for the "run" operator, Ghostscript first tries to open the file with the name as given, using the current working directory if no directory is specified. If this fails, and the file name doesn't specify an explicit directory or drive (for instance, doesn't contain "/" on Unix systems or "\" on DOS systems), Ghostscript tries directories in this order:  
 
1.
 the directories specified by the -I switches in the command line (see below), if any;  
2.
 the directories specified by the GS_LIB environment variable, if any;  
3.
 the directories specified by the GS_LIB_DEFAULT macro in the Ghostscript makefile when the executable was built. When gs is built on Unix, GS_LIB_DEFAULT is usually "/usr/share/ghostscript/#.##:/usr/share/ghostscript/fonts" where "#.##" represents the Ghostscript version number.  
 
 
 Each of these (GS_LIB_DEFAULT, GS_LIB, and -I parameter) may be either a single directory or a list of directories separated by ":".