Geographic Coordinate System Transformation

[VagelisFotopoulos]

Hello people i would like some suggestions to one of my problems. I have some layers in geographic coordinate system GGRS_87. Also i inserted a basemap and at first i tried to transform it from WGS_84 to GGRS_87 but the adjustment wasn't succesful. So i right clicked the icon "Layers" from Table of Contents went to properties and after this to the coordinate system tab in order to make right the transformation. What i saw was that the button transformations was missing. I repaired the programm, uninstalled and instaled it and nothing changed. Does anyone knows something about it? 

[DanPatterson]

it is available when you use the Project tool.

By default, the first layer you add to a map sets the coordinate system, subsequent layers are projected "on-the-fly" to it.

If you want data in the same coordinate system (vertical and horizontal transformations), you need to use the Project tool which makes new layers in the desired coordinate systems.

All of this requires that you data have a known, specified coordinate system to begin with.  If they don't you have to establish it using the Define Projection tool.  This tool does nothing but tell the layer what it is, not what you want it to be

[JayantaPoddar]

Could you open a new blank map? Add a couple of layers with different datums.

Open the data frame Properties > Coordinate System

Do you see the same issue (Transformations button missing)?

If the issue still persists, could you try Resetting your ArcGIS Application Profile?

You could contact your local Esri Support team if the issue doesn't get resolved by the above steps.