*DSpace log file:* {{\[dspace\]/log/dspace.log}}   (usually)

* *Tomcat log directory:* {{\[tomcat\]/logs}}   (usually)

* (_XMLUI Only_) *Cocoon log file:

* 
** DSpace 1.5.1 or previous: {{\[tomcat\]/webapps/<name-of-webapp>/WEB-INF/logs/}}

** DSpace 1.5.2 or later:  {{\[dspace\]/log/cocoon.log}}

h1. Resources

* DSpace technical FAQ: [TechnicalFaq]
* Browse dspace-tech mailing list: http://sourceforge.net/mailarchive/forum.php?forum=dspace-tech

* Search dspace-tech (or any DSpace mailing list): http://sourceforge.net/search/?group_id=19984&type_of_search=mlists

h1. General Instructions

# If the expected information simply never appears, leaving a blank browser screen, the problem is likely with either a servlet (for JSPUI) or an XSLT Theme (for XMLUI).  The error message should be in either {{\[dspace\]/log/dspace.log}} OR {{\[tomcat\]/logs/}}.  For the XMLUI, you may also want to check the Cocoon logs (see above for path) to see if any extra information can be found there.

# If you get an "Internal Server Error" message, you will have to check the log files for a full error listing. If your email address is set up in dspace.cfg ({alert.recipient}) as the DSpace Administrator, you should receive an email with this full error listing. If not, move into the DSpace log directory and view the end of the log file

:
#* (Linux or Mac OSX) Go to the DSpace log directory via the command line and enter: {{tail -100 dspace.log}}  Alternatively, you can open up the dspace.log file in your favorite text editor and look near the bottom of the file for the error message.
#* (Windows) Go to the DSpace log directory, and open dspace.log in your favorite text editor.  Look near the bottom for the error message.
# Usually, the culprit file is in the first five to ten lines of the error stack listing.  The error stack starts with a line similar to one of the following:
#* {{yyyy-mm-dd time WARN ...}} OR, 
#* {{yyyy-mm-dd time ERROR ...}}
# Search the [DSpace technical FAQ|TechnicalFaq] and the [dspace-tech mailing list|http://sourceforge.net/search/?group_id=19984&type_of_search=mlists] for information on the error. Key words in the error often are useful search terms. 
# If you'd like to try and do some debugging yourself, you can change the DSpace logger settings to {{DEBUG}} which will sometimes provide you with more information about the error.  To turn on debugging, visit the {{\[dspace\]/config/log4j.properties}} file and do the following:

#* To enable DEBUG logging in the {{dspace.log}} file, change the {{log4j.rootCategory}} and {{log4j.logger.org.dspace}} settings to {{DEBUG}} rather than {{INFO

}}.
#* (_XMLUI Only_) To enable DEBUG logging in the {{cocoon.log}} file, change the {{log4j.logger.org.apache.cocoon}} setting to {{DEBUG}} rather than {{INFO

}}.
#* *NOTE:* You'll need to restart Tomcat after enabling DEBUG mode in the {{log4j.properties}} file.

#* *WARNING:* Make sure to turn off debugging once you are finished.  Leaving debugging turned on will cause the log files to grow very large very quickly!

# If all else fails, email a description of the error along with the error stack listing to dspace-tech@lists.sourceforge.net.  Try to include the following in your email:

#* Your environment: Operating system, version of DSpace, version of Tomcat, Java, etc.

#* The exact steps you took to encounter the error

#* The error stack that you found in your log file