Print to PDF not creating pdf document

[#1]

Issue

After clicking the 'Print to PDF' button on a Nintex Form, a 'Converting to PDF' begins loading but no PDF file is created.

Error Code

Unable to convert to pdf. System.Exception: Could not start conversion. WinApi error code 1314. Check 'wnvinternal.dat' file has execute permissions and that it exists near wnvhtmltopdf.dll or set the WnvInternalFileName property with the full path of the file at Winnovative.HtmlToImageConverter.

Resolution

1. On your SharePoint server, open IIS manager and find the affected site App Pool
   • Determine the web application pool accounts used within your farm
2. Open Local Security Policy on one of your front end servers.
3. Under Local Policies, select User Rights Assignment.
4. Select "Replace a process level token" policy.
5. Add the web application pool accounts to the local policy. The accounts in question must be added directly; adding a group which has the account(s) as a member will not resolve the issue.

Additional Information

MSDN : “This security setting determines which user accounts can call the CreateProcessAsUser() application programming interface (API) so that one service can start another. “ 

Default accounts : Network Service, Local Service. 

The error in the SharePoint ULS logs :

12/19/2017 14:17:34.35 w3wp.exe (0x18DC) 0x1F08 Nintex Forms Front End 00000 Verbose Converting form to pdf ... 2826389e-6a0c-50b9-e9b1-743af6730a09 

12/19/2017 14:17:34.35 w3wp.exe (0x18DC) 0x1F08 Nintex Forms Front End 00000 Unexpected Unable to convert to pdf. System.Exception: Could not start conversion. WinApi error code 1314. Check 'wnvinternal.dat' file has execute permissions and that it exists near wnvhtmltopdf.dll or set the WnvInternalFileName property with the full path of the file at Winnovative.HtmlToImageConverter.?(String A_0, String A_1, String A_2, ?& A_3, Hashtable& A_4) at Winnovative.HtmlToPdfConverter.?(String A_0, String A_1, String A_2, String A_3, Boolean A_4) at Winnovative.HtmlToPdfConverter.?(Stream A_0, String A_1, String A_2, String A_3, String A_4, Boolean A_5) at Winnovative.HtmlToPdfConverter.?(String A_0, String A_1, String A_2, String A_3, Boolean A_4) at Winnovative.HtmlToPdfConverter.ConvertHtml(