Can not modify accounts in different languages

If you are not able to modify the cPanel account using different language other than English, then its a bug and the fix is not publicly released yet, for more details you can refer  below change log with case ID 59782

http://docs.cpanel.net/twiki/bin/view/AllDocumentation/ChangeLog/CPanelVersion1132

Unable to fetch the cPanel user file

If you ggetting the error "Unable to fetch the cPanel user file " while modifying account through WHM >> Modify Account then in order to get this issue resolved follow the steps:

Please log into root SSH on the machine and do the following:

cd /var/cpanel/users
ls -lah username
cat username

Here replace username with the cPanel username. The correct permissions on the file should look like the following

-rw-r----- 1 root username 596 Jun 8 14:03 username 

If the permissions are correct then check inside the file, the USER=username entry should have the username of that user. Some 3rd party plugins modify the username by appending .sometext to the end of the username. This can cause cPanel to be unable to read the user's file.