.NET: how to enable JIT debugger

andy7789 used Ask the Experts™
Hi X-perts,

I am trying to enable JIT dbugger for VB.NET applications. The run-time error window says:

"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

what i did

1) added

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

to two existing instances of  machine.config (for .NET v1.0.3705 and v2.0). I have added it before the closing </configuration>

I have also v3.0 and v3.5 under Windows/Microsoft.NET, but could not find any machine.config there

2) Checked "enable unmanaged code debugging" in the project properties

Still, it shows the same messages on errors and doesn't run JIT

Maybe I should uninstall all old .NETs and install the latest one?

Please, help

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

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I saw these links before. Still cannot make it work

1) added <system.windows.forms jitDebugging="true" /> to machine.config

2) added app.config file to the project and added the same JIT tag there

3) checked Tools-Options-Debugging; JIT is all checked

still it doesn't handle it
Try installing the .NET SDK and try again please.


(the link is for .net 2, but if you have vs2008 download the .net 3 or 3.5 sdk)
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I am a bit confused with all the .NETs on my computer

1) I can see v 1, v 2, v 3 and v 3.5
2) yesterday I installed SP1 for v 3.5
3) the error window lists the whole configuration and points to v.2, where I altered the machine config

it looks that it cannot see v 3 or v 3.5 and uses v 2


which SDK should I install? can I safely remove .NET 1 and 2?
Try installing 2 first, and if it doesnt work, install 3.5.


Installed 2.0.... the same problem. should try 3.5 shortly

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