diff --git a/src/backup/datastore.rs b/src/backup/datastore.rs
index 98db5772..7aef844c 100644
--- a/src/backup/datastore.rs
+++ b/src/backup/datastore.rs
@@ -11,7 +11,7 @@ use super::chunk_store::{ChunkStore, GarbageCollectionStatus};
 use super::dynamic_index::{DynamicIndexReader, DynamicIndexWriter};
 use super::fixed_index::{FixedIndexReader, FixedIndexWriter};
 use super::index::*;
-use super::DataBlob;
+use super::{DataBlob, ArchiveType, archive_type};
 use crate::config::datastore;
 use crate::server::WorkerTask;
 use crate::tools;
@@ -126,9 +126,9 @@ impl DataStore {
     {
         let filename = filename.as_ref();
         let out: Box<dyn IndexFile + Send> =
-            match filename.extension().and_then(|ext| ext.to_str()) {
-                Some("didx") => Box::new(self.open_dynamic_reader(filename)?),
-                Some("fidx") => Box::new(self.open_fixed_reader(filename)?),
+            match archive_type(filename)? {
+                ArchiveType::DynamicIndex => Box::new(self.open_dynamic_reader(filename)?),
+                ArchiveType::FixedIndex => Box::new(self.open_fixed_reader(filename)?),
                 _ => bail!("cannot open index file of unknown type: {:?}", filename),
             };
         Ok(out)
@@ -190,8 +190,8 @@ impl DataStore {
 
         for entry in walker.filter_entry(|e| !is_hidden(e)) {
             let path = entry?.into_path();
-            if let Some(ext) = path.extension() {
-                if ext == "fidx" || ext == "didx"{
+            if let Ok(archive_type) = archive_type(&path) {
+                if archive_type == ArchiveType::FixedIndex || archive_type == ArchiveType::DynamicIndex {
                     list.push(path);
                 }
             }
@@ -230,11 +230,11 @@ impl DataStore {
 
             tools::fail_on_shutdown()?;
 
-            if let Some(ext) = path.extension() {
-                if ext == "fidx" {
+            if let Ok(archive_type) = archive_type(&path) {
+                if archive_type == ArchiveType::FixedIndex {
                     let index = self.open_fixed_reader(&path)?;
                     self.index_mark_used_chunks(index, &path, status)?;
-                } else if ext == "didx" {
+                } else if archive_type == ArchiveType::DynamicIndex {
                     let index = self.open_dynamic_reader(&path)?;
                     self.index_mark_used_chunks(index, &path, status)?;
                 }
diff --git a/src/backup/manifest.rs b/src/backup/manifest.rs
index 7b9972a2..7eaa1704 100644
--- a/src/backup/manifest.rs
+++ b/src/backup/manifest.rs
@@ -1,5 +1,6 @@
 use failure::*;
 use std::convert::TryFrom;
+use std::path::Path;
 
 use serde_json::{json, Value};
 
@@ -7,10 +8,10 @@ use crate::backup::BackupDir;
 
 pub const MANIFEST_BLOB_NAME: &str = "index.json.blob";
 
-struct FileInfo {
-    filename: String,
-    size: u64,
-    csum: [u8; 32],
+pub struct FileInfo {
+    pub filename: String,
+    pub size: u64,
+    pub csum: [u8; 32],
 }
 
 pub struct BackupManifest {
@@ -18,14 +19,42 @@ pub struct BackupManifest {
     files: Vec<FileInfo>,
 }
 
+#[derive(PartialEq)]
+pub enum ArchiveType {
+    FixedIndex,
+    DynamicIndex,
+    Blob,
+}
+
+pub fn archive_type<P: AsRef<Path>>(
+    archive_name: P,
+) -> Result<ArchiveType, Error> {
+
+    let archive_name = archive_name.as_ref();
+    let archive_type = match archive_name.extension().and_then(|ext| ext.to_str()) {
+        Some("didx") => ArchiveType::DynamicIndex,
+        Some("fidx") => ArchiveType::FixedIndex,
+        Some("blob") => ArchiveType::Blob,
+        _ => bail!("unknown archive type: {:?}", archive_name),
+    };
+    Ok(archive_type)
+}
+
+
 impl BackupManifest {
 
     pub fn new(snapshot: BackupDir) -> Self {
         Self { files: Vec::new(), snapshot }
     }
 
-    pub fn add_file(&mut self, filename: String, size: u64, csum: [u8; 32]) {
+    pub fn add_file(&mut self, filename: String, size: u64, csum: [u8; 32]) -> Result<(), Error> {
+        let _archive_type = archive_type(&filename)?; // check type
         self.files.push(FileInfo { filename, size, csum });
+        Ok(())
+    }
+
+    pub fn files(&self) -> &[FileInfo] {
+        &self.files[..]
     }
 
     fn lookup_file_info(&self, name: &str) -> Result<&FileInfo, Error> {
@@ -86,15 +115,16 @@ impl TryFrom<Value> for BackupManifest {
 
             let snapshot = BackupDir::new(backup_type, backup_id, backup_time);
 
-            let mut files = Vec::new();
+            let mut manifest = BackupManifest::new(snapshot);
+
             for item in required_array_property(&data, "files")?.iter() {
                 let filename = required_string_property(item, "filename")?.to_owned();
                 let csum = required_string_property(item, "csum")?;
                 let csum = proxmox::tools::hex_to_digest(csum)?;
                 let size = required_integer_property(item, "size")? as u64;
-                files.push(FileInfo { filename, size, csum });
+                manifest.add_file(filename, size, csum)?;
             }
-            Ok(Self { files, snapshot })
+            Ok(manifest)
         }).map_err(|err: Error| format_err!("unable to parse backup manifest - {}", err))
 
     }
diff --git a/src/bin/proxmox-backup-client.rs b/src/bin/proxmox-backup-client.rs
index 721c21dc..8c5d060a 100644
--- a/src/bin/proxmox-backup-client.rs
+++ b/src/bin/proxmox-backup-client.rs
@@ -915,14 +915,14 @@ async fn create_backup(
                 let stats = client
                     .upload_blob_from_file(&filename, &target, crypt_config.clone(), true)
                     .await?;
-                manifest.add_file(target, stats.size, stats.csum);
+                manifest.add_file(target, stats.size, stats.csum)?;
             }
             BackupType::LOGFILE => { // fixme: remove - not needed anymore ?
                 println!("Upload log file '{}' to '{:?}' as {}", filename, repo, target);
                 let stats = client
                     .upload_blob_from_file(&filename, &target, crypt_config.clone(), true)
                     .await?;
-                manifest.add_file(target, stats.size, stats.csum);
+                manifest.add_file(target, stats.size, stats.csum)?;
             }
             BackupType::PXAR => {
                 println!("Upload directory '{}' to '{:?}' as {}", filename, repo, target);
@@ -938,7 +938,7 @@ async fn create_backup(
                     crypt_config.clone(),
                     catalog.clone(),
                 ).await?;
-                manifest.add_file(target, stats.size, stats.csum);
+                manifest.add_file(target, stats.size, stats.csum)?;
                 catalog.lock().unwrap().end_directory()?;
             }
             BackupType::IMAGE => {
@@ -952,7 +952,7 @@ async fn create_backup(
                     verbose,
                     crypt_config.clone(),
                 ).await?;
-                manifest.add_file(target, stats.size, stats.csum);
+                manifest.add_file(target, stats.size, stats.csum)?;
             }
         }
     }
@@ -969,7 +969,7 @@ async fn create_backup(
 
         let stats = catalog_result_rx.await??;
 
-        manifest.add_file(CATALOG_NAME.to_owned(), stats.size, stats.csum);
+        manifest.add_file(CATALOG_NAME.to_owned(), stats.size, stats.csum)?;
     }
 
     if let Some(rsa_encrypted_key) = rsa_encrypted_key {
@@ -978,7 +978,7 @@ async fn create_backup(
         let stats = client
             .upload_blob_from_data(rsa_encrypted_key, target, None, false, false)
             .await?;
-        manifest.add_file(format!("{}.blob", target), stats.size, stats.csum);
+        manifest.add_file(format!("{}.blob", target), stats.size, stats.csum)?;
 
         // openssl rsautl -decrypt -inkey master-private.pem -in rsa-encrypted.key -out t
         /*