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Some years ago I created a polygon coverage of Wexford Harbour in Ireland by tracing a rectified aerial image of the harbour using ArcGIS. Four tic points on the imagery were known locations; their positions were converted to Irish national grid (TM65) using an early version of GridInQuest. By georeferencing the image, the locations in the traced shapefile corresponded to Irish Grid.

In order to use ArcGIS online mapping features I needed to use IRENET95 so using its helpful guide I installed the package

ntv2-grids-master IG to ITM.

Using ArcToolbox I defined the projection as TM65_IG and attempted to project to IRENET95_Irish_Transverse_Mercator. Everything appeared to go perfectly; the box below Geographic Transformation displayed:

TM65_To_ETRS_1989NTv2 + IRENET95_To_ETRS_1989

When I pressed OK the process seemed to go to completion but I could not find the new, projected coverage anywhere. What is going on? I am baffled!

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I have resolved the question. I downloaded a shapefile of Co Wexford Historic Sites from http://webgis.archaeology.ie choosing IRENET95 ITM. I then created a new empty map document and added the shapefile to it. This set the data frame to IRENET95. I then added my TM-IG65 polygon shapefile whereupon ArcGIS offered to project the shapefile to IRENET95. This time the projection worked perfectly. I then removed the unwanted archaeology shapefile.

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