diff --git a/eris/eris/__main__.py b/eris/eris/__main__.py
index 1740345..741e61f 100755
--- a/eris/eris/__main__.py
+++ b/eris/eris/__main__.py
@@ -1090,8 +1090,11 @@ def manage_cache(root_path):
     cache_path = os.path.join(root_path, tools.CACHE_PATH)
     checksum_path = os.path.join(cache_path, "source_checksum")
     if os.path.exists(cache_path):
-        with open(checksum_path, "r") as checksum_file:
-            cache_checksum = checksum_file.read()
+        try:
+            with open(checksum_path, "r") as checksum_file:
+                cache_checksum = checksum_file.read()
+        except FileNotFoundError:
+            cache_checksum = None
         if source_checksum() != cache_checksum:
             print("Eris has changed, recalculating all results…")
             shutil.rmtree(cache_path)