Problem details:
when trying to install, writes osu! crashed and throws the following error:

See the end of this message for details on invoking
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
System.ComponentModel.Win32Exception (0x80004005): Не удается найти указанный файл
at System.Diagnostics.Process.StartWithShellExecuteEx(ProcessStartInfo startInfo)
at System.Diagnostics.Process.Start()
at System.Diagnostics.Process.Start(ProcessStartInfo startInfo)
at #=zRdS3azbCG2cp89JB4Q==.#=zum8N4JY=(Boolean #=zvqlN4U5t2DEn, Exception #=z4TnJW8c=)
at #=zXi_TMCx4cjTFCC_IXhzbk0k=.#=zmrq1piiMqr0I(Object #=zQ202Sdk=, EventArgs #=z4TnJW8c=)
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ButtonBase.WndProc(Message& m)
at System.Windows.Forms.Button.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)


************** Loaded Assemblies **************
mscorlib
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.18408 built by: FX451RTMGREL
CodeBase: file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/mscorlib.dll
----------------------------------------
osu!
Assembly Version: 0.0.0.0
Win32 Version: 1.3.3.8
CodeBase: file:///D:/Users/user/Desktop/HM2%20saves/osu!install.exe
----------------------------------------
System.Windows.Forms
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.18408 built by: FX451RTMGREL
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms/v4.0_4.0.0.0__b77a5c561934e089/System.Windows.Forms.dll
----------------------------------------
System.Drawing
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.18408 built by: FX451RTMGREL
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Drawing/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll
----------------------------------------
System
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.18408 built by: FX451RTMGREL
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System/v4.0_4.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
System.Core
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.18408 built by: FX451RTMGREL
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Core/v4.0_4.0.0.0__b77a5c561934e089/System.Core.dll
----------------------------------------
zx_1c64b35277084153ff74beb2ba2af8ac
Assembly Version: 0.0.0.0
Win32 Version: 1.3.3.8
CodeBase: file:///D:/Users/user/Desktop/HM2%20saves/osu!install.exe
----------------------------------------

************** JIT Debugging **************
To enable just-in-time (JIT) debugging, the .config file for this
application or computer (machine.config) must have the
jitDebugging value set in the system.windows.forms section.
The application must also be compiled with debugging
enabled.

For example:

<configuration>
<system.windows.forms jitDebugging="true" />
</configuration>

When JIT debugging is enabled, any unhandled exception
will be sent to the JIT debugger registered on the computer
rather than be handled by this dialog box.





Video or screenshot showing the problem:


osu! version: latest

What client are you trying to use, and how are you running it.
(also what OS are you on)

chromb wrote:

What client are you trying to use, and how are you running it.
(also what OS are you on)

OS - Windows 7
I downloaded a osu!install file from this site and tried to install the game

If you're trying to run osu!lazer, it won't run on windows 7. Upgrade to 8.1 or higher and it should work

Stable should work on anything

chromb wrote:

If you're trying to run osu!lazer, it won't run on windows 7. Upgrade to 8.1 or higher and it should work

Stable should work on anything

I try install stable, not lazer

Do you have any updates pending for your OS?

Do you have the most up-to-date versions for the .net framework? if no, try installing/updating to them.

https://dotnet.microsoft.com/en-us/download/dotnet-framework

Same here, getting the same error on Windows 7 too

Edit:

I managed to got it to work by updating the Windows root certificates and installing .NET Framework 4.7