First and foremost thing is to have the project artefacts available under a repository such as svn, cvs, or git.
At the end of the day, push it repository if any changes happened during the day. This way, projects are easy to manage, share with teams across locations and more importantly do not lose your work which might done over a period of time.
Coming to the issue, below is from your log:
Caused by: java.io.CharConversionException: Characters larger than 4 bytes are not supported: byte 0x87 implies a length of more than 4 bytes
You might have added some data with multibyte characters Yesterday.
Please try to open the project in a browser or in a text editor and see if you can correct so that it can be opened. Have a backup before making any edit.
Make sure you have utf-8 as file.encoding (you can check from Menu -> Help -> System Properties)
Please see
