diff --git a/src/backup/dynamic_index.rs b/src/backup/dynamic_index.rs
index 4374d37b..30e4e202 100644
--- a/src/backup/dynamic_index.rs
+++ b/src/backup/dynamic_index.rs
@@ -61,7 +61,8 @@ impl DynamicIndexReader {
 
     pub fn open(path: &Path) -> Result<Self, Error> {
 
-        let file = std::fs::File::open(&path)?;
+        let file = std::fs::File::open(&path)
+            .map_err(|err| format_err!("Unable to open dynamic index {:?} - {}", path, err))?;
 
         if let Err(err) = nix::fcntl::flock(file.as_raw_fd(), nix::fcntl::FlockArg::LockSharedNonblock) {
             bail!("unable to get shared lock on {:?} - {}", path, err);
diff --git a/src/backup/fixed_index.rs b/src/backup/fixed_index.rs
index 086efd56..a4d6213e 100644
--- a/src/backup/fixed_index.rs
+++ b/src/backup/fixed_index.rs
@@ -60,7 +60,8 @@ impl FixedIndexReader {
 
         let full_path = store.relative_path(path);
 
-        let mut file = File::open(&full_path)?;
+        let mut file = File::open(&full_path)
+            .map_err(|err| format_err!("Unable to open fixed index {:?} - {}", full_path, err))?;
 
         if let Err(err) = nix::fcntl::flock(file.as_raw_fd(), nix::fcntl::FlockArg::LockSharedNonblock) {
             bail!("unable to get shared lock on {:?} - {}", full_path, err);