diff --git a/.github/workflows/ubuntu-ci.yml b/.github/workflows/ubuntu-ci.yml
index fd46e6075b..b0d2a1449f 100644
--- a/.github/workflows/ubuntu-ci.yml
+++ b/.github/workflows/ubuntu-ci.yml
@@ -50,6 +50,20 @@ jobs:
         echo "/usr/local/cuda/bin" >> $GITHUB_PATH
         echo "LD_LIBRARY_PATH=/usr/local/cuda/lib64:$LD_LIBRARY_PATH" >> $GITHUB_ENV
         
+    - name: Clean vcpkg caches
+      run: |
+        rm -rf build/vcpkg_installed || true
+        rm -rf external/vcpkg/buildtrees || true
+        rm -rf external/vcpkg/packages || true
+        rm -rf external/vcpkg/downloads || true
+
+    - name: Clear proxy settings
+      run: |
+        echo "HTTP_PROXY=" >> $GITHUB_ENV
+        echo "HTTPS_PROXY=" >> $GITHUB_ENV
+        echo "http_proxy=" >> $GITHUB_ENV
+        echo "https_proxy=" >> $GITHUB_ENV
+
     - name: Bootstrap vcpkg
       run: |
         pushd external/vcpkg