diff --git a/internal/lsp/general.go b/internal/lsp/general.go
index dacce21351..003aef7cff 100644
--- a/internal/lsp/general.go
+++ b/internal/lsp/general.go
@@ -41,9 +41,18 @@ func (s *Server) initialize(ctx context.Context, params *protocol.ParamInitializ
 	source.SetOptions(&options, params.InitializationOptions)
 	options.ForClientCapabilities(params.Capabilities)
 
+	// gopls only supports URIs with a file:// scheme. Any other URIs will not
+	// work, so fail to initialize. See golang/go#40272.
 	if params.RootURI != "" && !params.RootURI.SpanURI().IsFile() {
 		return nil, fmt.Errorf("unsupported URI scheme: %v (gopls only supports file URIs)", params.RootURI)
 	}
+	for _, folder := range params.WorkspaceFolders {
+		uri := span.URIFromURI(folder.URI)
+		if !uri.IsFile() {
+			return nil, fmt.Errorf("unsupported URI scheme: %q (gopls only supports file URIs)", folder.URI)
+		}
+	}
+
 	s.pendingFolders = params.WorkspaceFolders
 	if len(s.pendingFolders) == 0 {
 		if params.RootURI != "" {