I tried to reply to similar posts, but couldn't figure out how to do it. So posting again: Galaxy giving this error when editing workflow, just after creating workflow from existing history: URL:http://localhost/galaxy/workflow/load_workflow?id=df7a1f0c02a5b08e&_=1352817462148 Moduleweberror.evalexception.middleware:*364*in|respond| |>> <http://localhost/galaxy/workflow/editor?id=df7a1f0c02a5b08e#>app_iter*=*self*.*application*(*environ*,*detect_start_response*)*| Modulepaste.debug.prints:*98*in|__call__| |>> <http://localhost/galaxy/workflow/editor?id=df7a1f0c02a5b08e#>environ*,*self*.*app*)*| Modulepaste.wsgilib:*539*in|intercept_output| |>> <http://localhost/galaxy/workflow/editor?id=df7a1f0c02a5b08e#>app_iter*=*application*(*environ*,*replacement_start_response*)*| Modulepaste.recursive:*80*in|__call__| |>> <http://localhost/galaxy/workflow/editor?id=df7a1f0c02a5b08e#>*return*self*.*application*(*environ*,*start_response*)*| Modulepaste.httpexceptions:*632*in|__call__| |>> <http://localhost/galaxy/workflow/editor?id=df7a1f0c02a5b08e#>*return*self*.*application*(*environ*,*start_response*)*| Modulegalaxy.web.framework.base:*160*in|__call__| |>> <http://localhost/galaxy/workflow/editor?id=df7a1f0c02a5b08e#>body*=*method*(*trans*,*****kwargs*)*| Modulegalaxy.web.framework:*73*in|decorator| |>> <http://localhost/galaxy/workflow/editor?id=df7a1f0c02a5b08e#>*return*simplejson*.*dumps*(*func*(*self*,*trans*,****args*,*****kwargs*)**)*| Modulegalaxy.webapps.galaxy.controllers.workflow:*733*in|load_workflow| |>> <http://localhost/galaxy/workflow/editor?id=df7a1f0c02a5b08e#>'tooltip'*:*module*.*get_tooltip*(*static_path*=*url_for*(*'/static'*)**)**,*| Modulegalaxy.workflow.modules:*258*in|get_tooltip| |>> <http://localhost/galaxy/workflow/editor?id=df7a1f0c02a5b08e#>*return*self*.*tool*.*help*.*render*(*static_path*=*static_path*)*| *AttributeError: 'NoneType' object has no attribute 'render'* Could anyone help me to solve this problem? Thanks, Sanjar.