Metadata reload and task execution in NPrinting 17 and 18 is extremely slow or fails. Bookmark issue.

The reload of metadata has become extremely slow and may fail after a long time.
The problem may occur only for some connections. It is possible that other connections, even connecting to the same source document are faster.
After enabling Interactive Service Detection it may be observed that QlikView Desktop UI does not show up in session 0 even though a qv.exe instance is shown active with memory usage oscillation in windows task manager.
Recently, this issue has also been see to cause the NPrinting Engine to Crash.

In the NPrinting Engine logs, error(s) similar to the one below may be registered:
...
Qlik.NPrinting.Engine 17.4.0.0 Qlik.NPrinting.Engine.Consumer.BlockingContentResolver 20190627T165853.815-04:00 WARN KKSVNPRINTING 0 0 0 0 0 0 0 0 Error while waiting consumer task and deleting navigator bookmark. ERROR:Object reference not set to an instance of an object. Stack trace:
...

Environment:

• NPrinting 17.3 / November 2017 / February 2018

 Product Defect ID

• OP-4261

Fix Version:

• NPrinting April 2018 and later versions

Diagnose:

• Check that folder. If the size of the files is over approximately 1MB:

Workaround fix:

• NPrinting creates some bookmarks files in this folder in the NPrinting Engine machine:

C:\Users\NPRINTING ENGINE USER NAME\AppData\Roaming\QlikTech\QlikView\Bookmarks

• A bookmark file is created for each connection and they are used to speed up the generation of metadata. If the size of these file increases too much (more than 1 MB), they became difficult to manage and they may block the metadata reload or cause severe performance decrease. In particular, opening the source application or applying filters become really time consuming or may fail.

 

• Stop the NPrinting Engine service
• Remove the bookmark(s) from the folder 

​​​​​​​C:\Users\NPRINTING ENGINE USER NAME\AppData\Roaming\QlikTech\QlikView\Bookmarks

• Restart the Engine service
• Reload the NPrinting metadata
• Performance should now be restored.

• Upgrade to the most recent version of NPrinting