I have already updated my MSFS2020 but this morning its updating again and the the progress bar is going from 5% to 10% to 20% then back to 4%...its like its not really downloading anything its yoyoing up and down.

Now its telling me I have a 17gig update..its like its installing MSFS all over again and when I loaded the game it was not in full screen but windowed

somethings wrong here. The first update is the mandatory update, I guess Navdata/AIRAC, when you start MSFS and it checks for these mandatory updates. Could it be that you have a custom MSFS install on another drive than c? just asking since there comes a tiny message with the first mandatory update and if you do not check the path it may have installed elsewhere but not into your (custom) MSFS folder. Thus screwing up your install and indeed trying to reinstall the sim again. 

The WU IX itself can be found in the Marketplace and would usually not mess around with your drives/folder settings

I do have a custom install on my F drive..whats odd is I got the update already with everyone else. Flew many times with it since the update even yesterday. Then this morning I launched it and the message for 17gig mandatory update showed up. Clicked the release notes and tells me about 1.25.9.0, which when I look at my sim version, thats the one I have.

I'm having the same issue as the original post - I have a 304 MB update that is taking forever to get through.  It looks like it is constantly restarting the download but the downloaded filename is changing (now on fs-base-0.1.163.fspatch.003....

 

Haven't gotten to the 17 gig update yet, but I suspect that it's coming.  My install is on my D drive.

Hmm, ok I thought I was an isolated incident, interesting. 

Same thing here, but it says the second update is 13GB (not 17)

4 minutes ago, Bill A said:

I do have a custom install on my F drive..whats odd is I got the update already with everyone else. Flew many times with it since the update even yesterday. Then this morning I launched it and the message for 17gig mandatory update showed up. Clicked the release notes and tells me about 1.25.9.0, which when I look at my sim version, thats the one I have.

I am not of any further help here I am afraid. Just suggest you stop whatever GB it tries to download and check your UserCfg.opt file, at the very end it tells your installed path. Mine says e.g. InstalledPackagesPath "F:\MSFS". Check what it says there and try to edit it to reflect your (custom) install path and try to start MSFS again. besides that I have no idea but others may chime in

Fine finished and Im back to flying...no idea what that was all about

I killed the first ongoing update and restarted - confirmed that the install folder was my D:\MSFS custom location.   The new update said it was 17GB, but it is now working through 13GB and progressing.  

Very strange.

1 minute ago, Bill A said:

Fine finished and Im back to flying...no idea what that was all about

fine then. worst case you have now a double MSFS installation, usually only noticed by a sudden decrease of disk space

had the same. 17 gig plus some gig for Italy....

My first update screen said 609.62 BIM

Some 300 MIB was installed ok.

MSFS then started OK.

The version is still 1.25.9

 

Update finally completed and all seems OK.  The default did change to windowed mode for me instead of full-screen so I needed to change that, but nothing else changed.  I had 10 gig of temporary files from the aborted first update attempt in my D:\MSFS2020\Official\OneStore folder that I deleted.

 

 

Did any of you uninstall some of the default aircraft, lessons, etc.  because if you did, periodically Asobo decides to reinstall them as an update, and BTW, changes all your settings to easy. Don't ask me how I know.