I tried it with admin privileges and astrometric alignment worked with the CR2 in the root of the C drive.
Using Astrometry.net (with admin priv), I get this error message in the console:
Trying it with admin privileges opening the CR2 file from the D: drive,0 [main] bash 1184 find_fast_cwd: WARNING: Couldn't compute FAST_CWD pointer. Please report this problem to
the public mailing list firstname.lastname@example.org
Reading input file 1 of 1: "C:/IMG_2827.fit"...
MS-DOS style path detected: C:/IMG_2827.fit
Preferred POSIX equivalent is: /cygdrive/c/IMG_2827.fit
CYGWIN environment variable option "nodosfilewarning" turns off this warning.
Consult the user's guide for more details about POSIX paths:
http://cygwin.com/cygwin-ug-net/using.h ... -pathnames
ERROR: Image type not recognized: Could not determine file type (does the file exist?): C:/IMG_2827.fit
augment-xylist.c:585:backtick Failed to run command: /usr/lib/astrometry/bin/image2pnm.py --no-fits2fits --fix-sdss --infile C:/IMG_2827.fit --uncompressed-outfile /tmp/tmp.uncompressed.ad8yFX --outfile /tmp/tmp.ppm.N05Zvp --ppm
ioutils.c:605:run_command_get_outputs Command failed: return value 255
Again in solves very quickly with astrometric aligment, but returns a similar error when trying an astrometry.net solve.