Error when installing pdf Text

[ppr]

I have the following error when trying to install PDF Text plugin:

An element set by the name "PDF Text" already exists. You must delete that element set to install this plugin.

This error is related in another post to the absence of poppler-utils. But in my case, I have poppler-utils installed on the server.

How can I fix it?

P-S : Omeka 2.5, php 7, Mysql 5.6.37

Plugins:

BulkMetadataEditor 2.4
Coins 2.0.3
CollectionTree 2.0
CsvImport 2.0.4
ExhibitBuilder 3.3.3
Geolocation 2.0.1
ItemRelations 2.0.2
Neatline 2.5.1
NeatlineSimile 2.0.4
NeatlineText 1.1.0
NeatlineWaypoints 2.0.2
OmekaApiImport 1.1.1
OpenLayersZoom 2.7.1
Reference 2.4.1
ShortcodeCarousel 1.0
SimpleContactForm 0.4
SimplePages 3.0.8
SimpleVocab 2.0.1
Stats 2.2.2
UniversalViewer 2.4.1

[jflatnes]

If you know you don’t have any PDF text data already, you can just go delete the “PDF Text” element set from Settings -> Element Sets.

[ppr]

Thanks! it is working!