Print To PDF not working on some forms after Update

[bzebarth]

We just updated Nintex Forms from 2.9.2.0 to 2.11.5.30. After the update some of our forms won't Print To PDF. On some of our forms the feature works fine but on others it comes up and says "Converting to PDF..." for a brief time and then that goes away but nothing happens. In Chrome we get the same message but it doesn't go away and nothing else happens. 

I reviewed the ULS logs and found the following error: "Unable to convert to pdf. System.Exception: HTML load error. Unknown network error at Winnovative.HtmlToImageConverter"

And "Application error when access /_layouts/15/nintexforms/PrintPdf.aspx, Error=Object reference not set to an instance of an object. at Nintex.Forms.SharePoint.ApplicationPages.PrintPdf.ProcessPdfResponse"

I've seen some other similar posts but the answers didn't seem to help. There are no background images on the form, I have tried removing all custom JS and CSS from the form, I have checked the "Replace a process level token" policy in Local Security Policies to make sure the Application Pool users are listed.

Can anyone think of any other possible causes for this?

[eharris04]

@bzebarth just to eliminate a few things, have you tried creating a basic form with no customizations and seeing if that works. 

In the past, updates to the browser have been shown to cause some issues with this feature. Try a basic form first, if that works, then we at least have a starting point to go from.

[sean_fiene]

When you click on Pring To PDF with the developer console open (F12) in Chrome, are any errors logged?

I'm wondering if it is looking for some asset on the form and the dev console can shed further light. 

Thank you,

Sean 

[bzebarth]

@eharris04 It works fine on some forms. We are still trying to determine if complexity or something else is what determines which forms work and which ones don't.

[eharris04]

I would recoommend following @sean_fiene suggestion. Complexity doesn't restrict that functionality.

[bzebarth]

@sean_fiene  I do get an error in Chrome, "Uncaught TypeError: Cannot read property 'PeopleManager' of undefined" but I don't get it in IE. I have forms that get this same error in Chrome but Print to PDF works in IE. 

[sean_fiene]

Oh perfect! Okay, on the form in question, are you using the UserProfileLookup() runtime function? Either in a rule or in a Calculated Value control? The PeopleManager error might be pointing to an issue with User Profile Service looking up information on the form. Either the referenced control or contextual value is not a appearing for the rule or formula.

[bzebarth]

That particular error is coming from a custom JS file that we have on all our forms, even the ones where PrintToPDF is working. The error doesn't show up in the IE dev console, which is the only browser I'm really concerned with because regular users don't have Chrome or Firefox.

Some additional testing seems to point to things like Rich Text fields, Repeating Sections and maybe Panels as things that when added to a form cause the Print To PDF functionality to stop working. I have confirmed that adding a Rich Text field breaks it but then changing it back to a plain text field, removing and re-adding the field and republishing fixes it. Some of the forms that aren't working don't have Rich Text fields but they do have Repeating Sections and Panels which I have not found on the forms that I know of that still work. I'll try adding those to my test form and see what happens.

[bzebarth]

@sean_fiene @eharris04  I think I have norrowed down the problem with the Print to PDF functionality to the following situations.

• If a form has a Multi-line Rich Text Field with data in it the Print function fails.
• If the list has a multi-line rich text field with rich text in it, whether or not that field is on the form the Print fails.
• If the form has a Repeating section that is connected to a Multi-Line text field (Plain Text) the Print fails. A repeating section that is not connected to a field does not seem to be a problem.
• If the form has a Panel with a rule that can hide it, whether or not it is hidden currently, the Print To PDF doesn't work. I can add hide rules to individual fields but not panels. The panel by itself with no rule seemed to be fine.
• If the form is in edit mode the print to pdf fails. (I think we had this issue before the update though)

[eharris04]

Thanks for the thorough notes. I have passed them along to one of the PMs for forms. I'll be sure to update this should something else pop up.