The one thing that you need to ask yourself is, if it is Asobo, why isn’t everyone experiencing this.
There are more than 2 million copies sold, and maybe a dozen or so postings of this.
With the ILS working in the vast majority of cases, it would stand to reason you just haven’t found the cause in your system yet.
It doesn’t seem setting related, but bear in mind settings are restored from the cloud with a reinstall.
Here is a link that may be a thing to try.
All - I have not tried ILS in MSFS in weeks, so I do not really know if it’s still working. The couple test flights I did, it worked just fine in the 747, after SU8. I cannot speak to the Garman units, so cannot help with those. For instance, in BA planes, it really helps if the FMS/C system has your information, because it works the AP system. SO, if no Flight Plan in computer, plane aint got a clue. For over year, ILS in Boeings was broken, but SU8 fixed lots of issues with it for me. I have not flown anything using any of the Garmin Units in over 16 months, SU’s and WU’s have changed them, I’m sure. Would have to start over from scratch. I had/continue to have this problem in X-Plane 11.
I haven’t noticed any problems with ILS capture
Well I tried the VCRUNTIME fix as suggested by @TheSevenflyer. Thanks Dude 
Now I’m uncertain if this was the actual fix, as I also programmed the FMC manually which was also a possible cause (SimBrief Import previously) and I have to confess, I flew the Mugz TBM with WT Garmin3000 mod all the way to the Runway with ILS capture !!!
I’m going to retry a Simbrief import next to narrow if the VCRUNTIME did help.
BTW the VCRUNTIME fix stuffed my FSUIPC and Navigraph Simlink installs, but simply re-installing Simlink seemed to resolve this.
I have ILS capture issues when at the end of a (around 1 hour) flight I’m being vectored to the runway (on VATSIM for instance). In this case flying in HDG and ALT mode the APPR mode will not become active while the light next to APP buttun is illuminated, it simply flies the selected heading and altitude. When I’m following a programmed SID and approach (so no HDG mode used) I do not have any issues, captures the ILS without any problem.
When I make a short testflight (take off and landing from same airport) only using HDG and ALT towards the ILS I don’t have an issue either, captures the ILS perfectly.
Mainly flying the TBM930 and Longitude, both with the WT G3000.
Did you try changing the GPS/Nav mode to nav?
Personal Comments
A couple of folks in other threads were also getting caught by a switchology error (or more like lack thereof): It’s not enough to pick up the LOC. If you’re on the LOC, you must switch to APR before the FAF, and be at the altitude constraint in order for GS to capture.
Yes, no solution unfortunately
When vectored to the approach I am at the prescribed / published altitude, trying to intercept the localizer before the faf. Arming APPR gives the indicator light next to the button on but the indicator light next to HDG knob remains on as well, so 2 lateral guidance modes active according to the AP panel. The FMA indicates loc and gs in white, they remain white and the aircraft shoots straight through the localizer.
This happens only when vectored after a flight of appr 1 hour or more. I have tbe idea that the more heading changes using HDG mode the bigger the chance of not capturing the localizer.
But which aircraft is this in?
Happens both in TBM930 and Longitude, both with the WT G3000 mod. Tried without this mod, same result. I read that with the WT mod the stock AP is used.
Yes, most WT Add-Ons rely upon the plane’s individual Autopilot PIDs.
Not sure what to tell you - I’ve flown the TBM with Mugz Mod and WT G3000 post SU8 and it works for ILS and RNAV approaches.
I’ll continu troubleshooting, try to find a reproducable scenario.
Ok…so there was an update today for the sim I think? Either that or it required me to update when I tried the suggestion earlier in this thread to delete the “fs-base-nav” folder and let it recreate upon sim startup. Anyway, I tried the 07L Approach to LAX with the TBM930 and it worked - but I had to toggle the gps/Loc setting back and forth a time or two to get it to take. Unfortunately I tried a second time with the new DC Design Concorde and couldn’t get it to work with that. I’d have to do further experimenting to see if things are working with the other planes again or if this is still a problem with only the Concorde. I know that the LAX Rwy 07L approach seems particularly difficult to hook up to. I’ve read that there is still a bug related to needing to toggle the gps/loc sometimes to get the plane to follow the localizer, but obviously this problem runs deeper than just that.
That was indeed a result of deleting the “fs-base-nav” folder.
Thanks TheSevenflyer, I’ve yet to do more experimenting but I don’t think it has solved my problems with this ILS/LOC problem. The Concorde works for others just as other planes like the TBM930 does. I’m guessing I still have this problem and hope there is a solution in the near future. I’ll continue to try things to fix this because it really detracts from enjoyment of MSFS.
Just installed SU9 and performed a flight in the WT Longitude. STAR arrival into ENBR with a lot of HDG changes, ILS capture without any problem. So careful conclusion: SU9 seems to have solved the issue.
I do confirm that on SU11 I’m still not able to let Concorde AP fly a VOR-ILS radial, of course setting all properly on AP as well as NAV freq and the rest. When selecting RAD, the HSI correctly indicated the VOR active but the FD on the ADI offsets a little bit and remained locked there. Engaging VOR/LOC or LAND mode does not make the aircraft steer, just remaining like it’s flying.
Very strange indeed they’ve still not solved it…