topic Re: Map projection switched to 'Unknown' while computer was idle in ArcGIS Pro Questions

Map projection switched to 'Unknown' while computer was idle

gis_mags — Thu, 09 Oct 2025 19:26:49 GMT

Hi all! Someone in my organization had an interesting experience today. They left a map open on their computer while they went to lunch and when they returned an hour later, the coordinate system on the map they had open had changed from NAD 1983 (2011) StatePlane Wisconsin South FIPS 4803 (US Feet) to 'Unknown.' They noticed immediately because all their data was now being placed in northern Congo.

The issue was easily resolved by changing the coordinate system back, but we are puzzled as to what caused the change. Apparently this happened to one other user a few months ago. Neither user has any reason to/knowledge of how to change their map projection. Has anyone ever seen this happen, or have any ideas about how user might do this on accident?

The map in question uses Workflow Manager to direct editors to make edits to a Utility Network. They are in ArcGIS Pro version 3.5.3 and Enterprise 11.3.0.

Re: Map projection switched to 'Unknown' while computer was idle

RTPL_AU — Thu, 09 Oct 2025 23:30:34 GMT

@gis_mags
I've had 3.5 crash a few times after getting back to a computer and unlocking it. Also seen behaviour that looks as if it takes a while for it to connect back to online services after an unlock - not long, just may need to refresh a map twice or it redraws a web service with tiles missing; then after a few seconds it's back to rendering as usual.

What you describe may be the result of the data itself not having a coordinate system assigned, and Pro losing the basemap on wakeup/unlock. It may then revert to Unknown as that is what the only other dataset in the map has.

In a more complex organisation there may be limitations on internet access while a pc is locked and a user's access is only granted again at login/unlock. A few seconds delay can get some waking processes out of sync and some apps don't handle it as gracefully as others.

I would double check that the data is set up properly and if the behaviour is the same with only local, located, data.

Your colleagues may have to be willing to go on multiple lunchbreaks per day until the problem is solved..... Issues like these can take years to resolve 🤣

Re: Map projection switched to 'Unknown' while computer was idle

gis_mags — Mon, 13 Oct 2025 21:26:01 GMT

First of all, correction - they are in Pro version 3.5.1.

In addition to the map projection being affected, a range of map settings are also being affected. For instance, label position and appearance settings change when this issue occurs, although label classes, expressions, and text symbol remain unchanged.

So far we have seen this issue occur three times and have not (yet) been able to recreate it.