Error: HTTP Error 500.21 - Internal Server Error, Handler UploadBsyn" has a bad module "ManagedPipelineHandler" in its module list Detailed Error InformationModule IIS Web Core. when uploading attachments to invoices"
When attempting to upload an attachment to invoices in WebInvoicing, you receive: HTTP Error 500.21 - Internal Server Error. Handler "UploadBsyn" has a bad module "ManagedPipelineHandler" in its module list
Most likely causes: ASP.NET is not installed or incompletely installed. A configuration typographical error occurred. Unfavorable pre-condition evaluation exists.
Things you can try: If ManagedPipelineHandler is missing, Ensure that ManagedEngine is in <globalModules>. ManagedPipelineHandler is in <handlers>, with correct pre-conditions. Install ASP.NET Ensure all system.webServer/handlers@modules system.webServer/handlers@modules are in system.webServer/modules@name Review pre-conditions in the <modules> and <handlers> sections.
Links and More Information IIS core does not recognize the module.
In IIS, change the Managed Pipeline Mode for the FEOnline application pool to use Integrated instead of Classic.