The error on the dashboard is simply a transaction rollback:

org.springframework.transaction.UnexpectedRollbackException: Transaction rolled back because it has been marked as rollback-only
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:626)
at com.atlassian.xwork.interceptors.XWorkTransactionInterceptor.intercept(XWorkTransactionInterceptor.java:132)

The underlying cause is this:

2007-10-10 18:29:27,981 ERROR [TP-Processor18] [renderer.v2.components.MacroRendererComponent] processMacro Unexpected error formatting macro: recently-updated
– url: /dashboard.action | userName: rosie@atlassian.com | action: dashboard
java.lang.RuntimeException: Multiple AttachmentData objects were returned when only one was expected
at com.atlassian.confluence.pages.persistence.dao.hibernate.HibernateAttachmentDataDao.getAttachmentDataForAttachment(HibernateAttachmentDataDao.java:66)
at com.atlassian.confluence.pages.persistence.dao.hibernate.HibernateAttachmentDataDao.getDataForAttachment(HibernateAttachmentDataDao.java:76)
at com.atlassian.confluence.pages.persistence.dao.hibernate.AbstractHibernateAttachmentDao.getAttachmentData(AbstractHibernateAttachmentDao.java:109)
at com.atlassian.confluence.pages.DefaultAttachmentManager.getAttachmentData(DefaultAttachmentManager.java:33)
at com.atlassian.confluence.pages.DelegatorAttachmentManager.getAttachmentData(DelegatorAttachmentManager.java:77)
at sun.reflect.GeneratedMethodAccessor286.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:296)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:177)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:144)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:107)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:166)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at $Proxy15.getAttachmentData(Unknown Source)
at com.atlassian.confluence.util.DefaultThumbnailInfoFactory.getThumbnailInfo(DefaultThumbnailInfoFactory.java:24)
at com.atlassian.confluence.renderer.radeox.macros.RecentlyUpdatedContentMacro.addThumbnailData(RecentlyUpdatedContentMacro.java:303)
at com.atlassian.confluence.renderer.radeox.macros.RecentlyUpdatedContentMacro.getChangeSets(RecentlyUpdatedContentMacro.java:253)
at com.atlassian.confluence.renderer.radeox.macros.RecentlyUpdatedContentMacro.getHtml(RecentlyUpdatedContentMacro.java:206)
at com.atlassian.confluence.renderer.radeox.macros.AbstractHtmlGeneratingMacro.execute(AbstractHtmlGeneratingMacro.java:42)
at com.atlassian.renderer.macro.RadeoxCompatibilityMacro.execute(RadeoxCompatibilityMacro.java:149)
at com.atlassian.confluence.renderer.v2.macros.RadeoxCompatibilityMacro.execute(RadeoxCompatibilityMacro.java:27)
at com.atlassian.renderer.v2.macro.ResourceAwareMacroDecorator.execute(ResourceAwareMacroDecorator.java:45)
at com.atlassian.renderer.v2.components.MacroRendererComponent.processMacro(MacroRendererComponent.java:254)
at com.atlassian.renderer.v2.components.MacroRendererComponent.makeMacro(MacroRendererComponent.java:150)
at com.atlassian.renderer.v2.components.WikiContentRendererHandler.handleMacro(WikiContentRendererHandler.java:18)
at com.atlassian.renderer.v2.WikiMarkupParser.makeMacro(WikiMarkupParser.java:126)
at com.atlassian.renderer.v2.WikiMarkupParser.makeMacro(WikiMarkupParser.java:114)
at com.atlassian.renderer.v2.WikiMarkupParser.handlePotentialMacro(WikiMarkupParser.java:99)
at com.atlassian.renderer.v2.WikiMarkupParser.parse(WikiMarkupParser.java:60)
at com.atlassian.renderer.v2.components.MacroRendererComponent.render(MacroRendererComponent.java:46)
at com.atlassian.renderer.v2.V2Renderer.render(V2Renderer.java:54)
at com.atlassian.renderer.v2.V2RendererFacade.convertWikiToXHtml(V2RendererFacade.java:57)
at sun.reflect.GeneratedMethodAccessor206.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:296)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:177)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:144)
at com.atlassian.spring.interceptors.SpringProfilingInterceptor.invoke(SpringProfilingInterceptor.java:20)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:166)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:107)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:166)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at $Proxy37.convertWikiToXHtml(Unknown Source)
at com.atlassian.confluence.renderer.DefaultWikiStyleRenderer.convertWikiToXHtml(DefaultWikiStyleRenderer.java:19)
at com.atlassian.confluence.themes.GlobalHelper.renderConfluenceMacro(GlobalHelper.java:149)
at sun.reflect.GeneratedMethodAccessor561.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.velocity.runtime.parser.node.ASTMethod.execute(ASTMethod.java:260)
at org.apache.velocity.runtime.parser.node.ASTReference.execute(ASTReference.java:207)
at org.apache.velocity.runtime.parser.node.ASTReference.render(ASTReference.java:250)
at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:94)
at org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:109)
at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:271)
at org.apache.velocity.Template.merge(Template.java:296)
at com.atlassian.confluence.util.velocity.VelocityUtils.getRenderedTemplateWithoutSwallowingErrors(VelocityUtils.java:53)
at com.atlassian.confluence.setup.velocity.ApplyDecoratorDirective.render(ApplyDecoratorDirective.java:229)
at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:153)
at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:271)
at org.apache.velocity.runtime.directive.VelocimacroProxy.render(VelocimacroProxy.java:215)
at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:153)
at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:94)
at org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:109)
at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:271)
at org.apache.velocity.Template.merge(Template.java:296)
at com.atlassian.confluence.util.velocity.VelocityUtils.getRenderedTemplateWithoutSwallowingErrors(VelocityUtils.java:53)
at com.atlassian.confluence.setup.velocity.ApplyDecoratorDirective.render(ApplyDecoratorDirective.java:229)
at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:153)
at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:271)
at org.apache.velocity.Template.merge(Template.java:296)
at com.opensymphony.webwork.dispatcher.VelocityResult.doExecute(VelocityResult.java:91)
at com.atlassian.xwork.results.ProfiledVelocityResult.doExecute(ProfiledVelocityResult.java:21)
at com.opensymphony.webwork.dispatcher.WebWorkResultSupport.execute(WebWorkResultSupport.java:116)
...