In my experience, I have seen many apps that are not designed to run for that long and simply require restarts. There may be an issue specifically with your Runtime version that can be addressed, but I have also seen it identified as an issue with the application being automated having memory leaks or other resource issues that simply don't present themselves to users because they are not using the app as much as a bot. I see that you have opened an SR, which is probably the best course of action.

Are you starting and stopping your IE adapter repeatedly? This can cause issues as well.