For whatever reason, you're having issues deleting a vROps Adapter Instance from the UI, here's how you do it from the vROps Suite-API.
Go to your vROps Suite-API URL: https://vrops_fqdn_or_ip/suite-api, which will re-direct you to https://vrops_fqdn_or_ip/suite-api/doc/swagger-ui/html. Mine looks like this.
Remember, vROps Suite-API documentation was converted to Swagger back in vROps 8.2. Once here, click the Authorize button to authenticate and enter your credentials.
You are now authenticated and can run commands against APIs. Here you can see all supported APIs, we'll focus on the Adapters API. Click Adapters - GET /api/adapters - Try it out
I'll run the default, but you could put the adapterKindKey in for the adapter kinds you want. The default looks like this.
It'll show all Adapter Instances, but I've searched for the Arista Adapter Instances I want to delete. Make note of the "id" field here, we will use this to delete the Adapter Instance later.
If you have many of them or just want to see all adapter instances of a certain kind, you can run the same GET using adapterKindKey of ARISTAEOS_ADAPTER in this case. If you're not sure what the adapterKindKey is, just search the original GET for them.
We now have the Adapter ID, let's delete it. Go to DELETE /api/adapters/{adapterId} and click Try it out.
Insert the adapterId and click Execute.
Response Code 204 indicates the Adapter Instance has been successfully deleted. Let's check our vROps UI. Before image on the left, after image on the right.
The power of the vROps Suite-API, use it!