After the last Postman update I'm getting the error in the title on the Collection Runner page. I have been running about the same number of collections as always, but I noticed an automatic update to Postman this morning (even though I have that setting turned off). I've viewed the changelog page as mentioned in other posts, but there is nothing on there to get the previous version. This is very frustrating and costing time and therefore money.
Tried to find info to downgrade to previous version but was not able to. I downloaded and ran the installer from the website anyway, but when I try to open Postman now I get an error "Version mismatch detected. Looks like you've used a newer version of the Postman app on this system. Please download the latest app and try again."
Are you running Windows like me!? Then the following might help you...
I wondered the same thing and searched the web for "postman portable". portapps.io has different versions of Postman ready to download and use, e.g. version 7.36 and version 8.0, as well as the latest version 10.8.
The portable versions should not cause problems like "Version mismatch detected" as all configuration is stored together with the app inside the same folder.