I tried to compile a (flawlessly working) LaTeX document on a different computer, and suddenly was faced with the above error message printed by the xparse package (after that, many errors follow).
I'm working on both computers with miktex 2.9 (and Texnic-Center) on Windows 7 (64 bit).
I tried EVERYTHING I found on stackexchange or anywhere else on the web, including:
- Updating all packages
- Removing the l3 packages and reinstalling them
- Doing the above for both the current user and in admin mode
- Removing the complete miktex distribution and re-installing it
- for only the current user
- for "anyone who uses this computer"
- with all packages
- only the basic packages
- Downloading the newest l3 packages manually from CTAN and copying them into the miktex folder
- Refreshing the FNDB and updating formats afterwards
Nothing worked. Right now, I'm just out of ideas. ANY suggestions??
EDIT: After performing UlrikeFischer's suggestion, I get different errors. After a long compilation process, this is the log file I get: