Same issue, also resolved by removing c# dev kit...
Error Debugging in Visual Studio Code: 'ConnectionLostException' when attempting to run C# code
![](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(153.6, 96%, 24%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3ELH%3C/text%3E%3C/svg%3E)
Ladislav Hochman
40
Reputation points
Visual Studio Code Version: 1.79
Operating System: Windows 11 Pro, 64-bit
Problem Description:
When attempting to debug C# code in Visual Studio Code, the following error message appears: "Your changes cannot be applied due to an unexpected error: ConnectionLostException. The 'next' operation was cancelled." This occurs both when pressing the F10 key and when clicking on 'Continue'. Until recently, everything was functioning without any problems. However, this issue suddenly emerged while coding and has persisted across different projects.
Developer technologies | Visual Studio | Debugging
Developer technologies | C#
{count} votes
-
Ladislav Hochman 40 Reputation points
2023-10-05T09:05:01.02+00:00 The problem was resolved by removing the C# Dev Kit extension.
-
Deleted
This comment has been deleted due to a violation of our Code of Conduct. The comment was manually reported or identified through automated detection before action was taken. Please refer to our Code of Conduct for more information.
-
![](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(115.19999999999999, 97%, 21%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EFS%3C/text%3E%3C/svg%3E)
Faisal Shaikh 5 Reputation points2023-10-12T17:12:36.9433333+00:00 The problem was resolved by removing the C# Dev Kit extension. Thanks @Ladislav Hochman
-
![](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(188.79999999999998, 34%, 28%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EJF%3C/text%3E%3C/svg%3E)
Jesualdo Flores Alvarado 10 Reputation points2024-11-25T18:10:11.15+00:00 I reinstalled the C# Dev extension :)
Sign in to comment
4 answers
Sort by: Most helpful
-
![](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(208, 97%, 30%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EP%3C/text%3E%3C/svg%3E)
Pete 10 Reputation points2023-10-13T15:40:33.42+00:00 -
![](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(179.20000000000002, 21%, 27%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EAW%3C/text%3E%3C/svg%3E)
Ardhio Wibowo 0 Reputation points2024-01-12T06:36:32.81+00:00 you don't have to remove it, try to install previous version. Debugging with C# Dev Kit 'v0.2.100' works in mine
-
![](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(118.4, 87%, 21%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EE%3C/text%3E%3C/svg%3E)
Egbertn 6 Reputation points2024-03-07T10:35:26.3266667+00:00 When will MSFT finally not release crappy releases? My productivity goes down due to bad quality of this c# dev kit.
It even caused me to not have a certain job due to VS being updated just before the interview, and all intellisense was gone.
-
![](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(147.20000000000002, 37%, 24%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3ESS%3C/text%3E%3C/svg%3E)
Sam Selfridge 1 Reputation point2025-08-22T02:43:36.0366667+00:00 Removing c# dev extension worked for me as well. For future googlers, this is the error I was getting in the debug console when my program started:
Exception: System.InvalidOperationException: Service IManagedEditAndContinueCsDevKitEngineService is unavailable.
Sign in to comment -
-
![](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(105.60000000000001, 25%, 20%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EVD%3C/text%3E%3C/svg%3E)
Velouria Denzer 0 Reputation points2025-08-22T06:09:12.1633333+00:00 so cool good job