Forum Discussion
Resolver IIGateway Error .Net Framework 4.30319 yet 4.8 is installed
Hey DKHUghes55 ,
This is one of those messages that looks scary but is actually a bit misleading at first glance so you’re not alone in questioning it.
The .NET version v4.0.30319 showing in the error does not mean your server is using .NET 4.0 instead of 4.8. In the world of .NET, versions from 4.5 all the way up to 4.8 are built as in-place upgrades on top of 4.0. Because of that, they all continue to report the same runtime version number (v4.0.30319). So even though your machine has .NET 4.8 installed, which is correct, the gateway process will still display that older-looking version string. That part is expected and not the problem.The real issue is the Mashup container crash coming from the On-premises data gateway. The message about Microsoft.Mashup.Container.NetFX45.exe and the FailFast call usually means the Power Query engine (which runs inside the gateway) hit something it couldn’t recover from and terminated itself.
In practical terms, this tends to point to things like a heavy or problematic query, resource pressure on the server, or sometimes even a bug in the specific gateway version you’re running. It’s less about the framework and more about what the gateway was doing at the time.
A good next step is to look into the gateway logs and try to connect the error to a specific dataset or refresh. You’ll usually find the logs under the gateway installation folder, and searching for “Mashup” or that error code can help pinpoint which query triggered it. If you can reproduce the same query in Power BI Desktop, that’s even better it often surfaces the underlying issue more clearly.
It’s also worth checking the basics on the server itself. If memory or CPU is getting pushed hard during refresh, the mashup container can crash like this. A quick restart of the gateway service and clearing temporary files can sometimes stabilize things, especially if this just started happening recently.
So in simple terms: your .NET setup is fine, the version number you’re seeing is normal, and the focus should shift to the query, data source, or gateway behavior at the time of failure. If you can narrow it down to a specific dataset or connector, it becomes much easier to diagnose further.
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Thanks for being part of the discussion!!!
Super UserThis is a common point of confusion — v4.0.30319 in the error doesn't mean .NET 4.0 is being used. That version string is actually the CLR (Common Language Runtime) version number, and it's been v4.0.30319 for all of .NET 4.x including 4.8. So 4.8 is almost certainly running correctly; the version string just looks outdated.
The real issue is the FailFast crash in the Mashup container with error code -2146233088 (which is 0x80131700 — a CLR initialization failure). That's what needs investigating.
A few things to check:
First, look at the gateway logs in %LOCALAPPDATA%\Microsoft\On-premises data gateway\GatewayLogs — the MashupContainer logs specifically will have more detail on what triggered the crash before the FailFast.
Second, check the Windows Event Viewer under Application logs around the time of the crash — there's often a more descriptive entry alongside the FailFast one.
Third, error code -2146233088 can sometimes be caused by a corrupted or missing .NET assembly, a TLS issue (the Mashup container making outbound calls that fail), or a memory/resource constraint on the server. If refreshes are happening in parallel, the container processes can starve resources.
Finally, since you're on the February gateway build, check if there's a March update available — there have been some Mashup container stability improvements recently. If the crashes are intermittent rather than consistent, it's likely a resource or timing issue rather than a configuration problem.