Is .Net backwards Compatible?


kncowans

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Hello all

Is .Net Backwards Compatible?

For Example, if I Install Version 9, can Older Versions then be Uninstalled?

Thanks in advance

Kevin
 
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can Older Versions then be Uninstalled?


Yes, if:
Your apps don’t explicitly depend on those older versions. You’ve updated your projects to target .NET 9 or newer. You’re not hosting legacy apps that require older runtimes, games also.
Microsoft provides a .NET Uninstall Tool to help safely remove outdated SDKs and runtimes. Just be cautious: uninstalling older versions may affect shared framework apps if they were built against those versions.

I would personally advise against it. There doesn’t seem to be a point, to me.

Some reading for you.

 

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Hello @antspants

Thanks for the Reply and the Information, it is appreciated.

It is more for the Future, this is a Clean Install, as I had a fair few Issues and everything is working Fine, now, for the moment at least.

Thanks

Kevin
 

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Cheers Kevin, various .Net versions are spread accross all sorts of crap. I’ll admit that it’s a bit of a mess, but I am sure someone will tell me I am wrong.

I suppose we can’t expect developers to update 30 year old (and earlier) software to keep up with the latest .Net.
After all, this isn’t Apple dictating terms to app makers.
 

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    Motherboard
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    32.0 GB of I forget and the box is in storage.
    Graphics Card(s)
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    OS on Samsung 1TB 870 QVO SATA
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    Case
    NZXT Phantom 820 Full-Tower Case
    Cooling
    Noctua NH-D15 Elite Class Dual Tower CPU Cooler / 6 x EziDIY 120mm / 2 x Corsair 140mm somethings / 1 x 140mm Thermaltake something / 2 x 200mm Corsair.
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    TP-Link BE9300 WiFi 7 Bluetooth 5.4 (Archer TBE550E)
    TP-Link TX201 V1 2.5GB Lan

    Grandstream HT812 - VoIP
    ASUS DSL-AX82U - Mesh
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    ASUS RT-BE88U Router

    Brother MFC-L2880DW Printer

    I’m on a horse.
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    Optimized with Dolby Atmos®
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    M.2 512GB
    Antivirus
    Defender / Malwarebytes
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    …still on a horse.
Hello @antspants

Apples stance on Apps is why I went Android for my Phone.

Kevin
 

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"Is .Net Backwards Compatible?"

Not really, an App may require a specific version/compatibility components downloaded during installation. That is likely to be an earlier version simply because Apps take time to develop.

It is difficult to determine what App needs what version or compatibility components, so best to just leave them.

The reference mentioned is for software developers, SDKs. Most users will not have those anyway.

I have versions from V1.0 upwards 32 bit, V2.0 upwards for 64 bit, some seem to be compatibility components. By todays standards older versions/compatibility components are pretty small.
 

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I would not delete any .NET packages. They are required for certain software to run, and they are usually installed with said software, and they are not always backwards compatible.

.NET 9 is not the same as .NET 4.8.1 (which seems to be the defacto standard right now).

I develop with .NET 9 and 10, but if I want maximum compatibility with say, libraries or DLLs, I may have to develop with 4.8.1. They are not cross compatible. At least in my experience. Keep in mind that Windows also uses .NET for some of its functions, and it's probably 4.8.1.

TL;DR:

Don't delete anything or your will break things.
 

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Hello @Catnip

Thanks for the Reply.

I have everything working Just Right now, with regards to .Net, so I will leave everything as it is.

I have my System Setup to Backup the PC to my Synology Nas Every Sunday (Active Backup for Business) and for my Synology Nas to perform Incremental Backups (Hyper Backup) Everyday to an External USB HDD.

All is Working Well, for now.

Thanks

Kevin
 

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Most run-time libraries like .NET are generally backwards compatible, and MS will assure you of that to justify installing their latest .NET. But there's a funny term in computing, it's called "bug compatibility".

Sometimes a group of software devs will get used to how a specific version of .NET or VC++ performs, even if that behavior isn't exactly 100% proper. So when a newer version of the .NET platform eventually corrects that behavior, older code may stop working. The new .NET isn't "bug compatible" with what the devs originally had in mind.

To prevent any unexpected compatibility issues, it's a common rule to install a few .NET versions in parallel (which it's designed to do). Typically a modern Windows system needs .NET 4.8 (or 4.8.1), 5, and maybe one of the higher versions if your app specifically requires it. You don't need all the versions stretching from 6 to 9.

.NET gets a major release in October of every year. So there will be a .NET 10 soon. Don't worry, you only really need 4.8 & 5 to survive at a minimum.
 

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