diff --git a/backend/nuget.config b/backend/nuget.config
index 765346e..be7b17d 100644
--- a/backend/nuget.config
+++ b/backend/nuget.config
@@ -4,4 +4,12 @@
     <clear />
     <add key="nuget.org" value="https://api.nuget.org/v3/index.json" />
   </packageSources>
+  <!-- Machine-wide VS installs (Microsoft.VisualStudio.FallbackLocation.config)
+       can register a fallback package folder on a drive that doesn't exist on
+       every dev machine (e.g. a D:\ that was only ever present on the machine
+       VS was originally installed on). Clearing it here makes restore/build
+       depend only on nuget.org, regardless of that machine-wide config. -->
+  <fallbackPackageFolders>
+    <clear />
+  </fallbackPackageFolders>
 </configuration>