I logged in as usual and entered the Orange arena. Upon entering, I noticed it took my system an unusually long time (approximately 2-3 minutes) to go from the loading screen to the arena itself. However, once it did finally load, I had multiple error popups. The first (top) was titled "Error" and stated "Host Connection Lost.". It was at this time that I noticed that in my chat window I had "Not receiving updates switching to TCP." I moved the top "Error" pop-up to find a second, third, fourth, and fifth pop-up, all titled "File Error". However, these had the error message "Unable to open settings/planes/f4u1d.pwl." I then shut down the game and restarted, getting the same results. I shut down again and this time tried running the Offline Arena, only getting the "File Error" message. I restarted the entire system, but to no avail.
To my knowledge, neither my system nor the game have had any changes recently (within the past few hours of this post) as I was running the game smoothly earlier in the day. If anyone can help, I would greatly appreciate it.