Could not load type 'APPortalUI.Web.HttpHandler.PdfHttpHandler'

WebViewer Version: 8.0

Do you have an issue with a specific file(s)? APPortalUI.Web.HttpHandler.PdfHttpHandler
Can you reproduce using one of our samples or online demos?
Are you using the WebViewer server? No
Does the issue only happen on certain browsers?
Is your issue related to a front-end framework?
Is your issue related to annotations?

Please give a brief summary of your issue:
(Think of this as an email subject)
Lots of could not load type ‘APPortalUI.Web.HttpHandler.PdfHttpHandler’ exceptions.

Please describe your issue and provide steps to reproduce it:
(The more descriptive your answer, the faster we are able to help you)
After upgrading to version 8.0 of the webviewer we are now noticing a lot of Could not load type ‘APPortalUI.Web.HttpHandler.PdfHttpHandler’. exceptions in our .NET MVC application. PDFs are still loading. But it is looking for this URL, which does not exist (the dk parameter changes each time, the rest seems to be the same): /Documents/FileViewerOrPublic/APPortal.axd?rt=2&dk=004D94928O6km6t3sl8ww4fFyWm1pxvgn&cn=ctl02_PdfControl&un=ctl02%24PdfControl&v=

Please provide a link to a minimal sample where the issue is reproducible:

This link works: Documents File: Public (Board) - BoardBook Premier

But again, from the frontend it appears to work just fine. The backend is where all the logs are being written.

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Thanks for contacting us for support. Since there is not much we can tell by looking the Frontend application, we need your assistant to help us to narrow down the issue:

When you say:

Can you be more specific? If you see this in your log, can you copy the entire log message?

For the URL:

Is this request comes from WebViewer library? If so, can you find which file is making this call?

This is our full log.

Unhandled exception raised.

System.Web.HttpException (0x80004005): Could not load type ‘APPortalUI.Web.HttpHandler.PdfHttpHandler’.
at System.Web.Compilation.BuildManager.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase)
at System.Web.Configuration.HandlerFactoryCache.GetTypeWithAssert(String type)
at System.Web.Configuration.HandlerFactoryCache.GetHandlerType(String type)
at System.Web.Configuration.HandlerFactoryCache…ctor(String type)
at System.Web.HttpApplication.GetFactory(String type)
at System.Web.HttpApplication.MaterializeHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.<>c__DisplayClass285_0.b__0()
at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

Yes, I believe this request appears to be coming from the WebViewer library, as nothing in our code hits APPortal or APPortal.axd directly. No, I don’t think I can find which file is making the call (I haven’t been able to reproduce the problem, though we have thousands of these errors in our logs over about 3 hours).

The first part of the URL (/Documents/FileViewerOrPublic) is from us. That’s the URL we use to serve up your webviewer; it returns the DIV (via JavaScript) and your JavaScript that ultimately loads .

Is APPortal in any way related to your WebViewer? If not, I may be barking up the wrong tree…

I couldn’t find anything related to APPortal.axd or APPortalUI or APPortal in WebViewer JavaScrit Library. I suggest you do a global search in your codebase to find this out.

Also, are you using and PDF SDK? If so, what language are you using?

We found the issue in another PDF application. Sorry for the confusion. Thanks for your help.