diff --git a/package.json b/package.json
index 678917d9db..7b1a7f2429 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "csharp",
   "publisher": "ms-vscode",
-  "version": "1.4.0-beta7",
+  "version": "1.4.0-beta8",
   "description": "C# for Visual Studio Code (powered by OmniSharp).",
   "displayName": "C#",
   "author": "Microsoft Corporation",
diff --git a/src/coreclr-debug/activate.ts b/src/coreclr-debug/activate.ts
index 0b76c18886..97e4d900a3 100644
--- a/src/coreclr-debug/activate.ts
+++ b/src/coreclr-debug/activate.ts
@@ -5,18 +5,26 @@
 'use strict';
 
 import * as vscode from 'vscode';
-import * as child_process from 'child_process';
 import * as fs from 'fs';
-import * as path from 'path';
 import TelemetryReporter from 'vscode-extension-telemetry';
 import { CoreClrDebugUtil } from './util';
 import * as debugInstall from './install';
 import { Platform, getCurrentPlatform } from './../platform';
+import * as semver from 'semver';
+
+const MINIMUM_SUPPORTED_DOTNET_CLI: string = '1.0.0-preview2-003121';
 
 let _reporter: TelemetryReporter = null;
 let _channel: vscode.OutputChannel = null;
 let _util: CoreClrDebugUtil = null;
 
+class DotnetInfo
+{
+    public Version: string;
+    public OsVersion: string;
+    public RuntimeId: string;
+}
+
 export function activate(context: vscode.ExtensionContext, reporter: TelemetryReporter) {
     _reporter = reporter;
     _channel = vscode.window.createOutputChannel('coreclr-debug');
@@ -27,22 +35,7 @@ export function activate(context: vscode.ExtensionContext, reporter: TelemetryRe
         return;
     }
 
-    let dotnetVersion: string = '';
-    let osVersion: string = '';
-    let osRID: string = '';
-    _util.spawnChildProcess('dotnet', ['--info'], _util.coreClrDebugDir(), (data: Buffer) => {
-        var lines: string[] = data.toString().replace(/\r/mg, '').split('\n');
-        lines.forEach(line => {
-            let match: RegExpMatchArray;
-            if (match = /^\ Version:\s*([^\s].*)$/.exec(line)) {
-                dotnetVersion = match[1];
-            } else if (match = /^\ OS Version:\s*([^\s].*)$/.exec(line)) {
-                osVersion = match[1];
-            } else if (match = /^\ RID:\s*([\w\-\.]+)$/.exec(line)) {
-                osRID = match[1];
-            }
-        });
-    }).then(() => {
+    checkForDotnetTools().then((dotnetInfo: DotnetInfo) => {
         let installer = new debugInstall.DebugInstaller(_util);
         _util.createInstallLog();
 
@@ -61,54 +54,98 @@ export function activate(context: vscode.ExtensionContext, reporter: TelemetryRe
             statusBarMessage.dispose();
             vscode.window.setStatusBarMessage('Successfully installed .NET Core Debugger.');
         }).catch((error: debugInstall.InstallError) => {
-                const viewLogMessage = "View Log";
-                vscode.window.showErrorMessage('Error while installing .NET Core Debugger.', viewLogMessage).then(value => {
-                    if (value === viewLogMessage) {
-                        _channel.show(vscode.ViewColumn.Three);
-                    }
-                });
-                statusBarMessage.dispose();
-
-                installStage = error.installStage;
-                installError = error.errorMessage;
-                moreErrors = error.hasMoreErrors ? 'true' : 'false';
-            }).then(() => {
-                // log telemetry and delete install begin file
-                logTelemetry('Acquisition', {
-                    installStage: installStage,
-                    installError: installError,
-                    moreErrors: moreErrors,
-                    dotnetVersion: dotnetVersion,
-                    osVersion: osVersion,
-                    osRID: osRID
-                });
-                try {
-                    deleteInstallBeginFile();
-                } catch (err) {
-                    // if this throws there's really nothing we can do
+            const viewLogMessage = "View Log";
+            vscode.window.showErrorMessage('Error while installing .NET Core Debugger.', viewLogMessage).then(value => {
+                if (value === viewLogMessage) {
+                    _channel.show(vscode.ViewColumn.Three);
                 }
-                _util.closeInstallLog();
             });
-    }).catch(() => {
-        const config = vscode.workspace.getConfiguration('csharp');
-        if (!config.get('suppressDotnetInstallWarning', false)) {
-            const getDotNetMessage = 'Get .NET CLI tools';
-            const goToSettingsMessage = 'Disable this message in user settings';
-            // Buttons are shown in right-to-left order, with a close button to the right of everything;
-            // getDotNetMessage will be the first button, then goToSettingsMessage, then the close button.
-            vscode.window.showErrorMessage('The .NET CLI tools cannot be located. .NET Core debugging will not be enabled. Make sure .NET CLI tools are installed and are on the path.',
-                goToSettingsMessage, getDotNetMessage).then(value => {
-                    if (value === getDotNetMessage) {
-                        let open = require('open');
-                        open('https://www.microsoft.com/net/core');
-                    } else if (value === goToSettingsMessage) {
-                        vscode.commands.executeCommand('workbench.action.openGlobalSettings');
-                    }
-                });
+            statusBarMessage.dispose();
+
+            installStage = error.installStage;
+            installError = error.errorMessage;
+            moreErrors = error.hasMoreErrors ? 'true' : 'false';
+        }).then(() => {
+            // log telemetry and delete install begin file
+            logTelemetry('Acquisition', {
+                installStage: installStage,
+                installError: installError,
+                moreErrors: moreErrors,
+                dotnetVersion: dotnetInfo.Version,
+                osVersion: dotnetInfo.OsVersion,
+                osRID: dotnetInfo.RuntimeId
+            });
+            try {
+                deleteInstallBeginFile();
+            } catch (err) {
+                // if this throws there's really nothing we can do
+            }
+            _util.closeInstallLog();
+        });
+    }).catch((error) => {
+        // log errors from checkForDotnetTools
+        _util.log(error.message);
+    });
+}
+
+// This function checks for the presence of dotnet on the path and ensures the Version
+// is new enough for us. Any error UI that needs to be displayed is handled by this function.
+// Returns: a promise that returns a DotnetInfo class
+// Throws: An Error() from the return promise if either dotnet does not exist or is too old. 
+function checkForDotnetTools() : Promise<DotnetInfo>
+{
+    let dotnetInfo = new DotnetInfo();
+
+    return _util.spawnChildProcess('dotnet', ['--info'], _util.coreClrDebugDir(), (data: Buffer) => {
+        let lines: string[] = data.toString().replace(/\r/mg, '').split('\n');
+        lines.forEach(line => {
+            let match: RegExpMatchArray;
+            if (match = /^\ Version:\s*([^\s].*)$/.exec(line)) {
+                dotnetInfo.Version = match[1];
+            } else if (match = /^\ OS Version:\s*([^\s].*)$/.exec(line)) {
+                dotnetInfo.OsVersion = match[1];
+            } else if (match = /^\ RID:\s*([\w\-\.]+)$/.exec(line)) {
+                dotnetInfo.RuntimeId = match[1];
+            }
+        });
+    }).catch((error) => {
+        // something went wrong with spawning 'dotnet --info'
+        let message = 'The .NET CLI tools cannot be located. .NET Core debugging will not be enabled. Make sure .NET CLI tools are installed and are on the path.';
+        showDotnetToolsWarning(message);
+        throw new Error("Failed to spawn 'dotnet --info'");
+    }).then(() => {
+        // succesfully spawned 'dotnet --info', check the Version
+        if (semver.lt(dotnetInfo.Version, MINIMUM_SUPPORTED_DOTNET_CLI))
+        {
+            let message = 'The .NET CLI tools on the path are too old. .NET Core debugging will not be enabled. The minimum supported version is ' + MINIMUM_SUPPORTED_DOTNET_CLI + '.';
+            showDotnetToolsWarning(message);
+            throw new Error("dotnet cli is too old");
         }
+
+        return dotnetInfo;
     });
 }
 
+function showDotnetToolsWarning(message: string) : void
+{
+    const config = vscode.workspace.getConfiguration('csharp');
+    if (!config.get('suppressDotnetInstallWarning', false)) {
+        const getDotNetMessage = 'Get .NET CLI tools';
+        const goToSettingsMessage = 'Disable this message in user settings';
+        // Buttons are shown in right-to-left order, with a close button to the right of everything;
+        // getDotNetMessage will be the first button, then goToSettingsMessage, then the close button.
+        vscode.window.showErrorMessage(message,
+            goToSettingsMessage, getDotNetMessage).then(value => {
+                if (value === getDotNetMessage) {
+                    let open = require('open');
+                    open('https://www.microsoft.com/net/core');
+                } else if (value === goToSettingsMessage) {
+                    vscode.commands.executeCommand('workbench.action.openGlobalSettings');
+                }
+            });
+    }
+}
+
 function logTelemetry(eventName: string, properties?: {[prop: string]: string}): void {
     if (_reporter !== null) {
         _reporter.sendTelemetryEvent('coreclr-debug/' + eventName, properties);
diff --git a/src/coreclr-debug/install.ts b/src/coreclr-debug/install.ts
index 07b978cc16..2b9ab59bed 100644
--- a/src/coreclr-debug/install.ts
+++ b/src/coreclr-debug/install.ts
@@ -7,7 +7,6 @@
 import { CoreClrDebugUtil } from './util';
 import * as fs from 'fs';
 import * as path from 'path';
-import * as child_process from 'child_process';
 import * as fs_extra from 'fs-extra-promise';
 
 export class InstallError extends Error {
@@ -53,14 +52,14 @@ export class DebugInstaller {
     }
 
     public install(runtimeId: string): Promise<void> {
-        var errorBuilder: InstallError = new InstallError();
+        let errorBuilder: InstallError = new InstallError();
         errorBuilder.installStage = 'writeProjectJson';
 
         return this.writeProjectJson(runtimeId).then(() => {
             errorBuilder.installStage = 'dotnetRestore';
             return this._util.spawnChildProcess('dotnet', ['--verbose', 'restore', '--configfile', 'NuGet.config'], this._util.coreClrDebugDir(),
                 (data: Buffer) => {
-                    var text: string = data.toString();
+                    let text: string = data.toString();
                     this._util.logRaw(text);
 
                     // Certain errors are only logged to stdout.
@@ -68,7 +67,7 @@ export class DebugInstaller {
                     DebugInstaller.parseRestoreErrors(text, errorBuilder);
                 },
                 (data: Buffer) => {
-                    var text: string = data.toString();
+                    let text: string = data.toString();
                     this._util.logRaw(text);
 
                     // Reference errors are sent to stderr at the end of restore.
@@ -78,7 +77,7 @@ export class DebugInstaller {
             errorBuilder.installStage = 'dotnetPublish';
             return this._util.spawnChildProcess('dotnet', ['--verbose', 'publish', '-r', runtimeId, '-o', this._util.debugAdapterDir()], this._util.coreClrDebugDir(),
                 (data: Buffer) => {
-                    var text: string = data.toString();
+                    let text: string = data.toString();
                     this._util.logRaw(text);
 
                     DebugInstaller.parsePublishErrors(text, errorBuilder);
@@ -253,7 +252,7 @@ export class DebugInstaller {
     }
 
     private static parseRestoreErrors(output: string, errorBuilder: InstallError): void {
-        var lines: string[] = output.replace(/\r/mg, '').split('\n');
+        let lines: string[] = output.replace(/\r/mg, '').split('\n');
         lines.forEach(line => {
             if (line.startsWith('error')) {
                 const connectionError: string = 'The server name or address could not be resolved';
@@ -271,16 +270,16 @@ export class DebugInstaller {
 
     private static parseReferenceErrors(output: string, errorBuilder: InstallError): void {
         // Reference errors are restated at the end of the output. Find this section first.
-        var errorRegionRegExp: RegExp = /^Errors in .*project\.json$/gm
-        var beginIndex: number = output.search(errorRegionRegExp);
-        var errorBlock: string = output.slice(beginIndex);
+        let errorRegionRegExp: RegExp = /^Errors in .*project\.json$/gm;
+        let beginIndex: number = output.search(errorRegionRegExp);
+        let errorBlock: string = output.slice(beginIndex);
 
-        var lines: string[] = errorBlock.replace(/\r/mg, '').split('\n');
+        let lines: string[] = errorBlock.replace(/\r/mg, '').split('\n');
         lines.forEach(line => {
-            var referenceRegExp: RegExp = /^(?:\t|\ \ \ \ )Unable to resolve '([^']+)'/g
-            var match: RegExpMatchArray;
+            let referenceRegExp: RegExp = /^(?:\t|\ \ \ \ )Unable to resolve '([^']+)'/g;
+            let match: RegExpMatchArray;
             while (match = referenceRegExp.exec(line)) {
-                var reference: string = match[1];
+                let reference: string = match[1];
                 if (reference.startsWith('Microsoft') ||
                     reference.startsWith('System') ||
                     reference.startsWith('NETStandard') ||
@@ -294,15 +293,15 @@ export class DebugInstaller {
     }
 
     private static parsePublishErrors(output: string, errorBuilder: InstallError): void {
-        var lines: string[] = output.replace(/\r/mg, '').split('\n');
+        let lines: string[] = output.replace(/\r/mg, '').split('\n');
         lines.forEach(line => {
-            var errorTypeRegExp: RegExp = /^([\w\.]+Exception)/g
-            var typeMatch: RegExpMatchArray;
+            const errorTypeRegExp: RegExp = /^([\w\.]+Exception)/g;
+            let typeMatch: RegExpMatchArray;
             while (typeMatch = errorTypeRegExp.exec(line)) {
-                var type: string = typeMatch[1];
+                let type: string = typeMatch[1];
                 if (type === 'System.IO.IOException') {
-                    var ioExceptionRegExp: RegExp = /System\.IO\.IOException: The process cannot access the file '(.*)' because it is being used by another process./g
-                    var ioMatch: RegExpMatchArray;
+                    const ioExceptionRegExp: RegExp = /System\.IO\.IOException: The process cannot access the file '(.*)' because it is being used by another process./g;
+                    let ioMatch: RegExpMatchArray;
                     if (ioMatch = ioExceptionRegExp.exec(line)) {
                         // Remove path as it may contain user information.
                         errorBuilder.errorMessage = `System.IO.IOException: unable to access '${path.basename(ioMatch[1])}'`;
diff --git a/src/coreclr-debug/util.ts b/src/coreclr-debug/util.ts
index a0470f5d2c..d15328ae5f 100644
--- a/src/coreclr-debug/util.ts
+++ b/src/coreclr-debug/util.ts
@@ -149,7 +149,7 @@ export class CoreClrDebugUtil
 
             child.on('error', (error: Error) => {
                 reject(error);
-            })
+            });
         });
 
         return promise;