An error is preventing Confluence from starting.

1. Open a command prompt. On Windows, do this by clicking on your Start menu, then click Run. In the Run box, type cmd and press OK
2. From the command prompt, go to your Confluence install directory
3. Go into the bin subdirectory
4. Run startup.bat and read the error message
5. Find a solution to the error below:

java.lang.NoClassDefFoundError IntraHibernateAttachmentCopier

If you are seeing the following error:

java.lang.NoClassDefFoundError: com/atlassian/confluence/pages/persistence/dao/hibernate/AbstractHibernateAttachmentDao$IntraHibernateAttachmentCopier

You have unzipped Confluence using a program that cannot handle long filenames. You must delete your install directory and go back to the point in the instructions that covers unzipping Confluence using a third-party unzip program.

Exception in thread "main" java.lang.NoClassDefFoundError: ...

If http://localhost:8090 goes to an error page when you run Confluence, go to the install directory and find the catalina.out log file (usually in the logs directory). If this file contains a single line error starting with "Exception in thread "main" java.lang.NoClassDefFoundError", your install path may contain spaces. The solution is to rename your install directory path so that there are no spaces, then restart Confluence.

Error creating Confluence Home directory

The confluence.home variable specified in confluence-init.properties cannot be created. To fix this, edit /confluence/WEB-INF/classes/confluence-init.properties and check that the specified path to the home directory exists. Make sure all the directory slashes use / and that the # has been removed at the beginning of the line. If you're stuck, try using confluence.home=c:/confluence/data.

JAVA_HOME environment variable is not defined correctly

You have not installed the Java Development Kit, or did not set the %JAVA_HOME% environment variable to the directory of the JDK. You should re-check your steps in Stage 2.

Port 8090 is in use

If you have another Confluence instance running on the same machine, you must edit <confluence-install-direcroty>/conf/server.xml and change both 8090 and 8000 to ports that do not conflict with your other Confluence instances, according to these instructions.

Error creating bean with name 'scheduler'

You may need to adjust your system time.

Error registering bean with name 'fileSystemAttachmentDataDao'

If you did not use one of the recommended unzipping tools, and happened to use for instance the default Windows XP extractor, one of the classes required for starting up Confluence may not be located due to the lengthy file-path. This is due to the default Windows tool silently failing to extract files with long names. We suggest you to use other tools such as WinZIP and 7zip and redo the deployment process.

Cause:
org.springframework.beans.factory.BeanDefinitionStoreException: Error registering bean with name 'fileSystemAttachmentDataDao' defined in class path resource [applicationContext.xml]: Class that bean class [com.atlassian.confluence.pages.persistence.dao.FileSystemAttachmentDataDao] depends on not found; nested exception is java.lang.NoClassDefFoundError: com/atlassian/confluence/pages/persistence/dao/FileSystemAttachmentDataDao$FileSystemAttachmentNamingStrategy
at org.springframework.beans.factory.xml.DefaultXmlBeanDefinitionParser.parseBeanDefinition(DefaultXmlBeanDefinitionParser.java:366)
caused by: java.lang.NoClassDefFoundError: com/atlassian/confluence/pages/persistence/dao/FileSystemAttachmentDataDao$FileSystemAttachmentNamingStrategy
at java.lang.Class.forName0(Native Method)