Developer technologies | Windows Forms
A set of .NET Framework managed libraries for developing graphical user interfaces.
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error object reference not set to an instance of an object in vb
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(19.2, 77%, 11%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EJS%3C/text%3E%3C/svg%3E)
Johnny's Laptop
5
Reputation points
Cannot view or edit form. getting an error message 'error object reference not set to an instance of an object' at
| StreamJsonRpc.JsonRpc.d__156`1.MoveNext() |
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Developer technologies | Windows Forms
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Viorel 127.3K Reputation points2026-10-13T09:06:39.2933333+00:00 In case of Visual Studio 2026, go to menu, TOOLS, Options, Preview Features, and try to unselect the option “Use the preview Windows Forms out-of-process designer for .NET apps”, and restart Visual Studio. If it does not help, then re-enable it back.
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![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(272, 75%, 36%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3END%3C/text%3E%3C/svg%3E)
Nguyen Dam (WICLOUD CORPORATION) 685 Reputation points Microsoft External Staff Moderator2026-10-13T02:26:22.0333333+00:00 Hello @Johnny's Laptop and thank you for reaching out.
The error message and stack trace currently provided do not contain enough information to identify the exact cause. Please provide:
- the full error log or stack trace
- the IDE or development environment you are using, including its version
- the version of .NET your project targets
- any relevant code and details about when the error occurs
- any recent changes made to the project
The more context you can provide, the easier it will be to troubleshoot the cause of the error.
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