diff --git a/crates/ecstore/src/store_api.rs b/crates/ecstore/src/store_api.rs
index 11270f6f..7ca9cdb8 100644
--- a/crates/ecstore/src/store_api.rs
+++ b/crates/ecstore/src/store_api.rs
@@ -276,7 +276,10 @@ impl HTTPRangeSpec {
             return Ok(range_length);
         }
 
-        Err(Error::other("range value invalid"))
+        Err(Error::other(format!(
+            "range value invalid: start={}, end={}, expected start <= end and end >= -1",
+            self.start, self.end
+        )))
     }
 }
 
diff --git a/crates/iam/src/manager.rs b/crates/iam/src/manager.rs
index b2907731..4d216a98 100644
--- a/crates/iam/src/manager.rs
+++ b/crates/iam/src/manager.rs
@@ -814,7 +814,7 @@ where
             let mp = MappedPolicy::new(policy);
             let (_, combined_policy_stmt) = filter_policies(&self.cache, &mp.policies, "temp");
             if combined_policy_stmt.is_empty() {
-                return Err(Error::other(format!("need policy not found {}", IamError::NoSuchPolicy)));
+                return Err(Error::other(format!("Required policy not found: {}", IamError::NoSuchPolicy)));
             }
 
             self.api
diff --git a/rustfs/src/storage/ecfs.rs b/rustfs/src/storage/ecfs.rs
index a9342970..46c3e0ed 100644
--- a/rustfs/src/storage/ecfs.rs
+++ b/rustfs/src/storage/ecfs.rs
@@ -740,7 +740,7 @@ impl S3 for FS {
 
         if let Some(part_num) = part_number {
             if part_num == 0 {
-                return Err(s3_error!(InvalidArgument, "part_number invalid"));
+                return Err(s3_error!(InvalidArgument, "Invalid part number: part number must be greater than 0"));
             }
         }
 
@@ -2707,7 +2707,10 @@ impl S3 for FS {
                 .finish()
                 .map_err(|e| s3_error!(InternalError, "writer output into json error, e: {}", e.to_string()))?;
         } else {
-            return Err(s3_error!(InvalidArgument, "unknown output format"));
+            return Err(s3_error!(
+                InvalidArgument,
+                "Unsupported output format. Supported formats are CSV and JSON"
+            ));
         }
 
         let (tx, rx) = mpsc::channel::<S3Result<SelectObjectContentEvent>>(2);
diff --git a/scripts/run.sh b/scripts/run.sh
index 44987d78..03eade1b 100755
--- a/scripts/run.sh
+++ b/scripts/run.sh
@@ -64,7 +64,6 @@ export RUSTFS_OBS_LOG_DIRECTORY="$current_dir/deploy/logs" # Log directory
 export RUSTFS_OBS_LOG_ROTATION_TIME="minute" # Log rotation time unit, can be "second", "minute", "hour", "day"
 export RUSTFS_OBS_LOG_ROTATION_SIZE_MB=1 # Log rotation size in MB
 
-#
 export RUSTFS_SINKS_FILE_PATH="$current_dir/deploy/logs/rustfs.log"
 export RUSTFS_SINKS_FILE_BUFFER_SIZE=12
 export RUSTFS_SINKS_FILE_FLUSH_INTERVAL_MS=1000