On Fri, May 29, 2015 at 6:30 PM, Ralf Mardorf <ralf.mardorf@xxxxxxxxxxxxxx> wrote: > On Fri, 29 May 2015 18:22:17 +0200, Damjan Georgievski wrote: >>> [rocketmouse@archlinux ~]$ claws-mail >> >>try >>[rocketmouse@archlinux ~]$ LANG=en_US.UTF-8 claws-mail > > Hi, > > [rocketmouse@archlinux ~]$ LANG=en_US.UTF-8 claws-mail > selecting folder '#mh/Claws Mail/The shared' > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > error: unknown encoding UTF8: using iso88591 as fallback > > It has got no side effects, everything is readable. > > Regards, > Ralf Since we ruled out system configuration problems, you will have to look through the files claws-mail would read for input as returned by $ strace -e open -o claws-mail.strace claws-mail When it loads and the error messages are there, you would just quit claws-mail again. My guess is that the problem lies in some gui toolkit configuration file, ~/.* or similar. You'll have to rule out any binary files and grep all plaintext files with this: $ grep -Po '(?<=")[^"]+(?=")' claws-mail.strace | while read file; do [[ -e "$file" ]] && file -b "$file" | grep -q text && grep UTF8 "$file"; done Get all string sequences between double quotes from the claws-mail strace log, check if it exists and is a text file using the libmagic-based file tool, then check if it contains your invalid string. You don't even deserve this solution, and you'll start sprae cheers! mar77i