Troubleshooting

Contents

Difficulty opening the project
Difficulty using the project
I’m having other problems. How do I contact the QGreenland team?

Difficulty opening the project 

If you’re having trouble opening the project, first ensure you’re using QGIS 3.16 LTR or greater. If you want to move QGreenland to a different location on your filesystem, move the entire directory; do not attempt to move only the .qgs/.qgz project file.

QGIS won’t start on OSX Catalina 

QGIS is currently not ‘notarized’ for Mac OSX. If you receive The developer of this app needs to update it to work with this version of macOS. Contact the developer for more information., then, in your OSX menus, try:

‘Security and Privacy’
‘Allow apps downloaded from…’
‘App Store and identified developers’
Locate QGIS here and select ‘Open anyway’

‘Unable to open’ from QGIS when opening project 

If you opened QGreenland from the command line, ensure you got the project name correct. E.g., from inside the unzipped QGreenland directory:

qgis qgreenland.qgs

No layers are present in the Layers Panel 

If you don’t see layers in the Layers Panel, you have not correctly opened a project. Click Project in the Menu Bar, then select Add Project, then navigate to your QGreenland directory, wherever you saved it, and open the .qgs/.qgz file inside.

Difficulty using the project 

After opening QGreenland, I only see blue ocean 

Right click on a layer in the Layers Panel that you’d like to view, and select Zoom to Layer.

If you experience this issue, please contact us with information about your Operating System and QGIS version. A small number of users have reported this issue, but we haven’t been able to identify the cause thus far.

`Too many open files` on Linux 

Your system may have multiple ways of limiting open files in different contexts. To check your limits:

ulimit -Sn  # soft limit
ulimit -Hn  # hard limit

Edit the /etc/security/limits.conf to add or update rules that apply to your user. If there are no rules, you can try adding:

* soft nofile 20480
* hard nofile 1048576

If your system uses systemd, also edit the /etc/systemd/system.conf and /etc/systemd/user.conf files to ensure the following variable is set to a large value in both files:

DefaultLimitNOFILE=20480

After applying these changes, you may find that new terminal windows are not affected. Reboot your computer to make the changes permanent.

I see `ERROR: Too many connections: max 64` in my terminal 

We don’t think this is an issue. This started happening when we switched to GeoPackages for vector data, but we’ve observed no negative impact of this error message.

The QGIS interface has no buttons or toolbars 

Right-click the toolbar area in the QGIS interface and check the toolbars you wish to turn on so that they are displayed. You can also go to View -> Toolbars in the Menu Bar.

I can’t see a layer in the Map View even though it’s turned on and I’ve zoomed to it 

Double-check that there is not another layer overlaying and thus obscuring the layer you want to see in the Map View. Remember that layer are displayed in the Map View in the same order that they are listed in the Layers Panel - layers listed at the top of the Layers Panel show up on top on the Map View. You can either turn off any layer that might be obscuring the layer you wish to see by unchecking it in the Layers Panel, or re-arrange the order of layers by clicking and dragging them up or down in the Layers Panel.

Some QGreenland data layers are only visible at a specific map scale (see QGreenland User Guide section 4.3.1: Scale-dependent rendering for more information). Try zooming in.

Navigating QGIS errors 

If you are opening QGIS using a terminal or using the QGIS Python console, it is possible you might see one of a few different error messages while using QGIS that the QGreenland team has determined can be ignored:

-Warning: Logged warning: Creating Warped VRT This error message is likely triggered by a raster layer in the QGreenland project but should not have any impact on the data layers or project usability.

-ERROR: Too many connections: max 64 This error is thought to be related to the GeoPackage file format but should not have any impact on the layers themselves or the project usability.

I’m having other problems. How do I contact the QGreenland team?

If you have feedback on or questions about the QGreenland data package, or want to contribute datasets to future QGreenland releases, please contact us at mailto:qgreenland.info@gmail.com.