I made a new webmap by choosing Save As option. Then added new layers and removed some old ones. The original 2020 map could be downloaded for offline use, but the new 2021 map cannot and does not have the "Enable offline mode" button in Settings. I went through all layers and they all have the "Enable Sync (required for offline use and collaboration)." I saw in other posts that people were talking about the basemap, but that is the same ESRI world imagery as in the orginal map so dont think that can be the issue. Other posts also mentioned Enterprise, but we are not Enterprise.
We are trying to use it in Collector Classic and Collector, but it shouldnt really matter since the problem is that I dont get the option to enable offline use of the 2021 map.
Hope someone can help
This is my pre-flight checklist:
☑ At least one layer must be editable
☑ All layers need to be sync-enabled
☑ The basemap must support "export tiles"
☑ The map and layers must be shared with a group
☑ The map must be configured for offline use
If you have done all that, it will help diagnose the issue. If it still does not work offline, I would use a binary search to see if there is a problem layer; remove half the layers from a map (except at least one editable layer) and then see if it works.