diff --git a/.github/workflows/e2e-tests.yml b/.github/workflows/e2e-tests.yml
index 36fd1ef..f3588e8 100644
--- a/.github/workflows/e2e-tests.yml
+++ b/.github/workflows/e2e-tests.yml
@@ -177,17 +177,17 @@ jobs:
       - name: Clear toolcache
         shell: pwsh
         run: __tests__/clear-toolcache.ps1 ${{ runner.os }}
-      - name: Setup dotnet '3.1.1xx'
+      - name: Setup dotnet '5.0.1xx'
         uses: ./
         with:
-          dotnet-version: '3.1.1xx'
-      - name: Setup dotnet '6.0.3xx'
+          dotnet-version: '5.0.1xx'
+      - name: Setup dotnet '7.0.1xx'
         uses: ./
         with:
-          dotnet-version: '6.0.3xx'
+          dotnet-version: '7.0.1xx'
       - name: Verify dotnet
         shell: pwsh
-        run: __tests__/verify-dotnet.ps1 3.1.1 6.0.3
+        run: __tests__/verify-dotnet.ps1 5.0.1 7.0.1
 
   test-setup-global-json-specified-and-version:
     runs-on: ${{ matrix.operating-system }}
diff --git a/__tests__/installer.test.ts b/__tests__/installer.test.ts
index 6c20afe..363310c 100644
--- a/__tests__/installer.test.ts
+++ b/__tests__/installer.test.ts
@@ -201,7 +201,6 @@ describe('DotnetVersionResolver tests', () => {
     '.2.3',
     '.2.x',
     '*.',
-    '*',
     '1.2.',
     '1.2.-abc',
     'a.b',
@@ -222,7 +221,7 @@ describe('DotnetVersionResolver tests', () => {
     }
   );
 
-  each(['3.1', '3.1.x', '3.1.*', '3.1.X', '3.1.1xx']).test(
+  each(['3.1', '3.1.x', '3.1.*', '3.1.X', '5.0.1xx']).test(
     "if version: '%s' that can be resolved to 'channel' option is supplied, it should set type to 'channel' in version object",
     async version => {
       const dotnetVersionResolver = new installer.DotnetVersionResolver(
diff --git a/dist/index.js b/dist/index.js
index bc00897..ed522cc 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -250,33 +250,51 @@ class DotnetVersionResolver {
     }
     resolveVersionInput() {
         return __awaiter(this, void 0, void 0, function* () {
-            const isLatestPatchSyntax = /^\d+\.\d+\.\d{1}x{2}$/.test(this.inputVersion);
-            if (!semver_1.default.validRange(this.inputVersion) && !isLatestPatchSyntax) {
+            if (!semver_1.default.validRange(this.inputVersion) && !this.isLatestPatchSyntax()) {
                 throw new Error(`'dotnet-version' was supplied in invalid format: ${this.inputVersion}! Supported syntax: A.B.C, A.B, A.B.x, A, A.x, A.B.Cxx`);
             }
             if (semver_1.default.valid(this.inputVersion)) {
-                this.resolvedArgument.type = 'version';
-                this.resolvedArgument.value = this.inputVersion;
+                this.createVersionArgument();
             }
             else {
-                this.resolvedArgument.type = 'channel';
-                const [major, minor] = this.inputVersion.split('.');
-                if (isLatestPatchSyntax) {
-                    this.resolvedArgument.value = this.inputVersion;
-                }
-                else if (this.isNumericTag(major) && this.isNumericTag(minor)) {
-                    this.resolvedArgument.value = `${major}.${minor}`;
-                }
-                else {
-                    this.resolvedArgument.value = yield this.getLatestByMajorTag(major);
-                }
-                this.resolvedArgument.qualityFlag = +major >= 6 ? true : false;
+                yield this.createChannelArgument();
             }
         });
     }
     isNumericTag(versionTag) {
         return /^\d+$/.test(versionTag);
     }
+    isLatestPatchSyntax() {
+        var _b, _c;
+        const majorTag = (_c = (_b = this.inputVersion.match(/^(?<majorTag>\d+)\.\d+\.\d{1}x{2}$/)) === null || _b === void 0 ? void 0 : _b.groups) === null || _c === void 0 ? void 0 : _c.majorTag;
+        if (majorTag && parseInt(majorTag) < 5) {
+            throw new Error(`'dotnet-version' was supplied in invalid format: ${this.inputVersion}! The A.B.Cxx syntax is available since the .NET 5.0 release.`);
+        }
+        return majorTag ? true : false;
+    }
+    createVersionArgument() {
+        this.resolvedArgument.type = 'version';
+        this.resolvedArgument.value = this.inputVersion;
+    }
+    createChannelArgument() {
+        return __awaiter(this, void 0, void 0, function* () {
+            this.resolvedArgument.type = 'channel';
+            const [major, minor] = this.inputVersion.split('.');
+            if (this.isLatestPatchSyntax()) {
+                this.resolvedArgument.value = this.inputVersion;
+            }
+            else if (this.isNumericTag(major) && this.isNumericTag(minor)) {
+                this.resolvedArgument.value = `${major}.${minor}`;
+            }
+            else if (this.isNumericTag(major)) {
+                this.resolvedArgument.value = yield this.getLatestByMajorTag(major);
+            }
+            else {
+                this.resolvedArgument.value = 'LTS';
+            }
+            this.resolvedArgument.qualityFlag = +major >= 6 ? true : false;
+        });
+    }
     createDotNetVersion() {
         return __awaiter(this, void 0, void 0, function* () {
             yield this.resolveVersionInput();
diff --git a/src/installer.ts b/src/installer.ts
index 22fa100..9b85f7b 100644
--- a/src/installer.ts
+++ b/src/installer.ts
@@ -27,26 +27,15 @@ export class DotnetVersionResolver {
   }
 
   private async resolveVersionInput(): Promise<void> {
-    const isLatestPatchSyntax = /^\d+\.\d+\.\d{1}x{2}$/.test(this.inputVersion);
-    if (!semver.validRange(this.inputVersion) && !isLatestPatchSyntax) {
+    if (!semver.validRange(this.inputVersion) && !this.isLatestPatchSyntax()) {
       throw new Error(
         `'dotnet-version' was supplied in invalid format: ${this.inputVersion}! Supported syntax: A.B.C, A.B, A.B.x, A, A.x, A.B.Cxx`
       );
     }
     if (semver.valid(this.inputVersion)) {
-      this.resolvedArgument.type = 'version';
-      this.resolvedArgument.value = this.inputVersion;
+      this.createVersionArgument();
     } else {
-      this.resolvedArgument.type = 'channel';
-      const [major, minor] = this.inputVersion.split('.');
-      if (isLatestPatchSyntax) {
-        this.resolvedArgument.value = this.inputVersion;
-      } else if (this.isNumericTag(major) && this.isNumericTag(minor)) {
-        this.resolvedArgument.value = `${major}.${minor}`;
-      } else {
-        this.resolvedArgument.value = await this.getLatestByMajorTag(major);
-      }
-      this.resolvedArgument.qualityFlag = +major >= 6 ? true : false;
+      await this.createChannelArgument();
     }
   }
 
@@ -54,6 +43,38 @@ export class DotnetVersionResolver {
     return /^\d+$/.test(versionTag);
   }
 
+  private isLatestPatchSyntax() {
+    const majorTag = this.inputVersion.match(
+      /^(?<majorTag>\d+)\.\d+\.\d{1}x{2}$/
+    )?.groups?.majorTag;
+    if (majorTag && parseInt(majorTag) < 5) {
+      throw new Error(
+        `'dotnet-version' was supplied in invalid format: ${this.inputVersion}! The A.B.Cxx syntax is available since the .NET 5.0 release.`
+      );
+    }
+    return majorTag ? true : false;
+  }
+
+  private createVersionArgument() {
+    this.resolvedArgument.type = 'version';
+    this.resolvedArgument.value = this.inputVersion;
+  }
+
+  private async createChannelArgument() {
+    this.resolvedArgument.type = 'channel';
+    const [major, minor] = this.inputVersion.split('.');
+    if (this.isLatestPatchSyntax()) {
+      this.resolvedArgument.value = this.inputVersion;
+    } else if (this.isNumericTag(major) && this.isNumericTag(minor)) {
+      this.resolvedArgument.value = `${major}.${minor}`;
+    } else if (this.isNumericTag(major)) {
+      this.resolvedArgument.value = await this.getLatestByMajorTag(major);
+    } else {
+      this.resolvedArgument.value = 'LTS';
+    }
+    this.resolvedArgument.qualityFlag = +major >= 6 ? true : false;
+  }
+
   public async createDotNetVersion(): Promise<DotnetVersion> {
     await this.resolveVersionInput();
     if (!this.resolvedArgument.type) {