I am trying to convert a raster layer to a polygon layer using QGIS 3.16. 2. When I open the polygonize tool, the program does not allow me to select any existing raster layers from the 'Input layer' drop-down menu.
I have tried manually selecting the raster from my computer (a .TIF tile), but just get the following message:
The Log Messages window does't seem to offer any further information, at least in the OGR tab, reading:
2021-01-16T11:42:49 WARNING Cannot open C:/Users/User/Desktop/GBG_slope.tif.()
I am not sure what's happening here. What potential ways can I solve this issue?