Malicious Software Removal Tool Update KB890830

I'm trying to understand this November 2017 Malicious Software Removal Tool Update. It was in Important Updates but the Install Box was not Checked. It seems from THIS link that it's only function is to Run the Malicious Software Removal Tool, OR, is it also the Definition Update? And, do I need it at all when I already run Avast and MBAM? Is this why it is not checked, because they assume most are running Third Party AV/AM? I can't believe I don't know about this tool very well.

I now see that it is the same KB Number every month, and has installed before somehow without my Checking it, is that possible? Honestly, I could have checked it a few times, but it is showing that it has installed every month as expected.

Is it because I have "Give me Updates for Microsoft Products and check for new Optional Microsoft software when I update windows" Checked in Update Settings.

Thanks 7 lovers!

Thanks Ranger4 I will go ahead and run it today! But, is it really worth running if other scans are being done? And the download time and resources it takes if one is wanting to do other work?

I will do just that Ranger4, because you have much more experience than I, and I certainly don't want an infection on my Main Machine!

Thanks, Nasty7

I'd caution very strongly against immediately installing this month's MSRT.

First, it's bad practice in my view to check and install updates that MS have unchecked. They do that for a reason, typically because problems have been encountered that may lead them to hot-fix or withdraw the update and meanwhile they don't want it automatically installed by the unwary.

Second, there have indeed been problems already reported with this particular update:-

Issues with Microsofts Tech and Windows World

Third, there are so many potential pitfalls with any and all of MS's updates these days that there is no merit whatsoever in installing anything less than a critical update against a zero-day problem (that is, an exploit or other form of malware that is already active in the public domain as opposed to a vulnerability that is merely theoretical but not yet seen in the real world) until several days at least have elapsed during which time any problems with the updates will have been reported and those updates either hot-fixed or withdrawn. Some wait until the weekend after Patch Tuesday, personally I wait until around the end of the month and then follow the recommendations of various technical sites (including this one).

In any event, my understanding of the MSRT is that it plays no part in preventing future infections but merely finds certain of the more prominent infections if you already have them. If you are already adequately protected then while it adds an additional element to your protection it won't find anything that shouldn't already have been picked up by your other anti-virus/malware software. Like all of MS's updates, however, we are fast approaching the point with this particular update where the risk of it damaging your computer may outweigh the risks from not installing it! In short, most users experience more "malware" from MS than from any other source!

So feel free to install the MSRT immediately, and please let us know how you get on, but my advice is to wait a little, not only as there have already been problems reported with it, but also because it will have been unchecked for a reason, and it is in any event not recommended that you check and install unchecked updates - without at least looking into them and establishing why they are unchecked and whether they are strictly necessary.

All of the above relates to Important Updates. It is rare for them to be unchecked, and that fact alone should raise suspicions whenever it happens. Optional Updates, on the other hand, will generally - subject to your settings - be unchecked and should definitely never be installed unless you have a very clear reason to do so. In particular, third party updates such as graphics drivers should only ever be installed if you need them from the manufacturer's website and not through Windows Updates. I also include MSE updates in that and only ever run them from MSE and not through Windows Updates.

@Seffrid, that sounds like very sound advice and that is why I came here and asked, so thank you very much. I did Install it and will report back if anything bad happens.