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Using old plans and maps that I rectified and georeferenced I determined approximate coordinates for certain points. These coordinates are in decimal degrees and are split in two colums latitude and longitude in the relevant excel table. Now I imported the excel table in xls format and set the coordinate system to WGS84 Web Mercator, and while the relative position of the points to each other seems correct, their absolute position is wrong; they are in the middle of the base map and not in Belgium, which does obviously not exist in the ocean near Africa.

What am I doing wrong?

I was under the impression that WGS84 web mercator was the default setting for ArcMap10. I also tried exporting the imported xls into a shapefile. Or am I doing something wrong with the excel since every time I get a 'ArcMap drawing Errors: one or more layers failed to draw. syntax error (missing operator) in query expression ' notification. I tried changing the ',' into '.' in the DD notation but then my computer reads it as numbers instead of coordinates.

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    It would help if you could include a few lines of your excel file in the question but it sounds like your coordinates are not formatted correctly and are being imported with a lat/long of zero/zero, which would put them off the west coast of Africa south of Ghana. – Dan C Mar 6 '18 at 16:54
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    Don't set the coordinate system in the "add xy data" dialog to Web Mercator. Set it to WGS84 or whatever GCS you georeferenced the points to. Once they're in, you can do a data>export data into web mercator if you want. – mkennedy Mar 6 '18 at 19:39
  • 1 3.460004 51.088056 AMUG_0089 keramiek (objectgenre) This is an example from my excel file (3.46004 is the longitude colum; 51.088056 is the latitude colum). I changed the settings to the american notation (dots instead of comma's) and I no longer have the synthax issue but the points are still located south of Ghana. – Sophie Mar 7 '18 at 9:13
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    Using the comment on the format from Dan I figured it could be solved by importing it as a CSV-file since it nullifies the formatting issue. I also added the CSV to GCS-WGS_84 as mkennedy proposed and now the point are into the correct place once exported into a shapefile! thank you very much for your assistance! – Sophie Mar 7 '18 at 9:58
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    Sophie--you might write up a quick answer stating the solution so we can up vote it! – mkennedy Mar 7 '18 at 18:59
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Using the comment on the format from Dan I figured it could be solved by importing it as a CSV-file since it nullifies the formatting issue. While ArcMap 10 accepts xls files I figured it could still have problems with the format like using a . Or , as a decimal separator; having cells recognized as text instead of number type; having spaces typed after the numbers etc. Instead of trying to change all variables I trusted good ol' CSV. I also added the CSV as a GCS-WGS_84 coordinatesystem as mkennedy proposed. I was not aware that there were so many options to selects for WGS_84. Now the point are into the correct place once exported into a shapefile! Thank you very much for your assistance and guidance!

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