I saw file looping for the first time last week. Not on my own FS computer, but on a new Alienware system, which is actually much more powerful than my own. I have a 200MB cable internet connection at home, and have never had the slightest problem downloading the base sim, or any of the world updates. WU4 downloaded at 100MB (average) speed, and took about 45 minutes total.
A friend recently purchased the new Alienware computer mainly to run MSFS. He lives in a rural area outside of the city, and his only internet option is via satellite. His bandwidth is pretty good, but his service has a hard data cap of 80GB per month, making initial install of the sim impossible via his own ISP.
When he received his new computer, I brought it to my house to do the initial install of MSFS using my cable internet. It downloaded every bit as fast as my own computer does - averaging 100MB. I installed the base sim (Premium Deluxe version), as well as WU1, 2 and 3. The whole process took less than 4 hours. He then took the computer home, and reported that it worked very well on his satellite internet service.
Then WU4 was released… A couple of days later, he called me to report that (as expected), his MSFS automatically started downloading WU4 and “it seems to be stuck”. Apparently it had been trying to download the same file over and over for two days. I figured that the issue was his satellite connection, and when he checked his ISP app, he discovered that he was over his monthly data limit.
So, he brought his computer back to my house, and I connected to my unlimited internet. The very same router and modem I use for my own MSFS system every day, and the very same connection I used to do his initial install just a few weeks ago. To my surprise, when I launched MSFS, it started looping on the very first file. I also noted that the bandwidth of the connection on the update progress bar was showing only 5MB.
I asked if he had changed any of the data settings in the sim, and he said that yes, he had changed the bandwidth from “unlimited” to 5 MB (the lowest setting), because he found that otherwise, MSFS would “hog” all his satellite bandwith and interfered with streaming apps used by other family members.
This was a classic Catch 22 situation. It seemed evident that the file looping was caused by his MSFS data bandwidth settings being lowered to minimum - but the only way to change that would be to have a fully functioning sim - and there was no way to get to that point because it was stuck in an infinite update loop. AFAIK, the data settings are stored in the cloud, and cannot be changed on the local machine without a fully functioning MSFS.
What I finally did to fix it was to log him out of the X-Box app, and logged in using my own credentials. Since we both own the same version of MSFS, once logged in under my own gamer tag, my own personal settings were applied to the local copy of MSFS, including my bandwidth setting of “unlimited”.
Sure enough, once I launched MSFS (as me), it immediately started downloading WU4 at full speed of 100MB, with no looping or hesitation whatsoever. Once the update was complete, I shutdown the sim, logged out of the X-Box app, and had my friend log back in with his own ID. I relaunched, MSFS, and once it was loaded, confirmed that his bandwidth was indeed set to 5 MB. I told him to try a higher setting at home, to see if he can find something that won’t bog down his satellite connection, or at least set it back to “unlimited” before any scheduled major sim update.
I know that some users have solved looping downloads by limiting bandwidth using a external program like NetLimiter, but in this case, the limited bandwith settings in MSFS itself was 100 percent responsible for the download problem.
External limiters may have their place, but based on this experience, I do not think it is wise to ever set MSFS own internal bandwith to anything other than “unlimited”. If I had not been able to “rescue” the situation by temporarily taking ownership of his MSFS installation by logging into X-Box under my own ID, he might have lost access to the sim permanently, because the critical setting causing the issue was locked away in the cloud and unreachable without a fully-updated sim.