diff --git a/src/snapshot_middleware/csv.rs b/src/snapshot_middleware/csv.rs
index 3b38c3aa..fe3e6753 100644
--- a/src/snapshot_middleware/csv.rs
+++ b/src/snapshot_middleware/csv.rs
@@ -10,6 +10,7 @@ use crate::{
 };
 
 use super::{
+    error::SnapshotError,
     meta_file::AdjacentMetadata,
     middleware::{SnapshotFileResult, SnapshotInstanceResult, SnapshotMiddleware},
 };
@@ -25,9 +26,14 @@ impl SnapshotMiddleware for SnapshotCsv {
             return Ok(None);
         }
 
-        let file_name = entry.path().file_name().unwrap().to_string_lossy();
+        let extension = match entry.path().extension() {
+            Some(x) => x
+                .to_str()
+                .ok_or_else(|| SnapshotError::file_name_bad_unicode(entry.path()))?,
+            None => return Ok(None),
+        };
 
-        if !file_name.ends_with(".csv") {
+        if extension != "csv" {
             return Ok(None);
         }
 
@@ -35,7 +41,8 @@ impl SnapshotMiddleware for SnapshotCsv {
             .path()
             .file_stem()
             .expect("Could not extract file stem")
-            .to_string_lossy()
+            .to_str()
+            .ok_or_else(|| SnapshotError::file_name_bad_unicode(entry.path()))?
             .to_string();
 
         let meta_path = entry
diff --git a/src/snapshot_middleware/dir.rs b/src/snapshot_middleware/dir.rs
index 9c365594..970cc92b 100644
--- a/src/snapshot_middleware/dir.rs
+++ b/src/snapshot_middleware/dir.rs
@@ -8,6 +8,7 @@ use crate::{
 };
 
 use super::{
+    error::SnapshotError,
     middleware::{SnapshotFileResult, SnapshotInstanceResult, SnapshotMiddleware},
     snapshot_from_imfs, snapshot_from_instance,
 };
@@ -38,7 +39,7 @@ impl SnapshotMiddleware for SnapshotDir {
             .file_name()
             .expect("Could not extract file name")
             .to_str()
-            .unwrap()
+            .ok_or_else(|| SnapshotError::file_name_bad_unicode(entry.path()))?
             .to_string();
 
         Ok(Some(InstanceSnapshot {
diff --git a/src/snapshot_middleware/txt.rs b/src/snapshot_middleware/txt.rs
index f76e4e6d..a939a100 100644
--- a/src/snapshot_middleware/txt.rs
+++ b/src/snapshot_middleware/txt.rs
@@ -9,6 +9,7 @@ use crate::{
 };
 
 use super::{
+    error::SnapshotError,
     meta_file::AdjacentMetadata,
     middleware::{SnapshotFileResult, SnapshotInstanceResult, SnapshotMiddleware},
 };
@@ -25,7 +26,9 @@ impl SnapshotMiddleware for SnapshotTxt {
         }
 
         let extension = match entry.path().extension() {
-            Some(x) => x.to_str().unwrap(),
+            Some(x) => x
+                .to_str()
+                .ok_or_else(|| SnapshotError::file_name_bad_unicode(entry.path()))?,
             None => return Ok(None),
         };
 
@@ -38,12 +41,12 @@ impl SnapshotMiddleware for SnapshotTxt {
             .file_stem()
             .expect("Could not extract file stem")
             .to_str()
-            .unwrap()
+            .ok_or_else(|| SnapshotError::file_name_bad_unicode(entry.path()))?
             .to_string();
 
         let contents = entry.contents(imfs)?;
         let contents_str = str::from_utf8(contents)
-            .expect("File content was not valid UTF-8")
+            .map_err(|err| SnapshotError::file_contents_bad_unicode(err, entry.path()))?
             .to_string();
 
         let properties = hashmap! {