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Brand new QGIS user here. I'm on version 2.12.3 on a Win7 machine.

I've downloaded a vector layer as part of an assignment. After adding an OpenStreetMap base layer, the project placed my vector feature somewhere in Nigeria, when it's supposed to be in Navarro, the US.

What is likely to be the problem here? Both layers are on the WGS 84 / Pseudo Mercator (EPSG:3857), and I have OTF projections turned on.

addendum:

CRS for OpenStreetMaps layer

CRS for vector features

  • Your vector layer is almost certainly not in EPSG:3857 but in epsg:4326 – Ian Turton Aug 5 '16 at 8:07
  • I've checked. they're the same! I've added the screenshots to my post above for your reference – huajiet Aug 8 '16 at 14:56
  • What is the extent of the vector layer, as reported by rightclick on the layer -> Properties -> Metadata tab -> Properties section? – AndreJ Aug 8 '16 at 18:47
  • In layer spatial reference system units xMin,yMin 379098.27,1570600.97 : xMax,yMax 731300.27,2194830.56 – huajiet Aug 9 '16 at 2:57
  • Layer Spatial Reference System +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs – huajiet Aug 9 '16 at 2:57
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Set Layer CRS does NOT reproject coordinates.

If the shapefile was in some kind of US State Plane coordinate system, you have to leave it in that.

On-the-fly reprojection assures that it overlays with a basemap in another CRS. If necessary, you can reproject to another filename and different CRS unsing Save As ....

Usually, shapefiles come with a .prj file containing the CRS information. If that is missing, you have to assign the projection yourself. For Navarro, Texas, it should have been Texas North Central EPSG:32138 in meters or EPSG:2276 in US-feet. But both do not fit to the extent you give. So you have to ask the data provider for the correct CRS.

BTW QGIS 2.12.3 is a bit outdated, we have QGIS 2.16.1 as current release.

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You activated the On The Fly (OTF) projection, but your layers are not in the same projection. The second layer you add is reprojected to be displayed with the same projection as your first layer, but as the coordinates doesn't match your layer is diplayed far away from the US. To fix the projection of your layer, you need to save it as a new layer and specify the projection you want.

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