diff --git a/src/main.rs b/src/main.rs
index bceb1c6..7c3d4e9 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -4,7 +4,7 @@ use std::{
     fmt::Display,
     fs::{self, File},
     io::{self, BufRead, BufReader},
-    path::{self, Path, PathBuf},
+    path::{self, PathBuf},
     str::FromStr,
 };
 
@@ -351,11 +351,12 @@ impl PsbQaqcResult {
 //         .collect_vec()
 // }
 
-fn write_psbqaqc_csv(result: MasterLogResult, outfile: PathBuf) -> Result<()> {
+/// If `nonewfile` is `true`, out file is not created when there is already a file.
+fn write_psbqaqc_csv(result: MasterLogResult, outfile: PathBuf, nonewfile: bool) -> Result<()> {
     let expanded_results = PsbQaqcResult::from_masterlogresult(result);
 
-    let mut wtr = match outfile.exists() {
-        true => {
+    let mut wtr = match (outfile.exists(), nonewfile) {
+        (true, false) => {
             let file = File::options()
                 .read(true)
                 .append(true)
@@ -364,7 +365,7 @@ fn write_psbqaqc_csv(result: MasterLogResult, outfile: PathBuf) -> Result<()> {
                 .has_headers(false)
                 .from_writer(file)
         }
-        false => {
+        (false, _) => {
             println!("Creating new file: {}", outfile.display());
             let file = File::options()
                 .create_new(true)
@@ -374,6 +375,10 @@ fn write_psbqaqc_csv(result: MasterLogResult, outfile: PathBuf) -> Result<()> {
                 .has_headers(true)
                 .from_writer(file)
         }
+        (true, true) => {
+            error!("Out file already exists but specified not to make new file");
+            return Err(anyhow!("Out file already exists"));
+        }
     };
     for result in expanded_results {
         wtr.serialize(result)?;
@@ -409,7 +414,7 @@ fn main() -> Result<()> {
 
             let outfile = outfile.unwrap_or(get_output_filename(&result));
 
-            write_psbqaqc_csv(result, outfile.clone())?;
+            write_psbqaqc_csv(result, outfile.clone(), true)?;
 
             println!("Add comments about errors in the last column of the CSV file");
             println!("Press any key to start editting...");
@@ -428,14 +433,17 @@ fn main() -> Result<()> {
                     editor
                 }
                 (None, Err(e1), Err(e2)) => {
-                    info!("No VISUAL nor EDITOR found, {}, {}", e1, e2);
+                    warn!("No VISUAL nor EDITOR found, {}, {}", e1, e2);
+                    warn!("Using `nano` as a fallback editor");
                     "nano".to_string()
                 }
             };
             std::process::Command::new(editor)
                 .arg(outfile.clone())
-                .spawn()?
-                .wait()?;
+                .spawn()
+                .context("Error during spawning editor")?
+                .wait()
+                .context("Error while waiting editor")?;
 
             {
                 let f = File::open(outfile.clone())?;
@@ -444,7 +452,7 @@ fn main() -> Result<()> {
             }
             println!();
             println!("Copy the CSV above and paste it to the database(Google sheets)");
-            println!("Choose Data->Split text to columns to format it");
+            println!("Choose `Data->Split text to columns` to format it");
 
             println!("Press any key when upload finished...");
             terminal::enable_raw_mode()?;
@@ -483,7 +491,7 @@ fn main() -> Result<()> {
 
             let outfile = outfile.unwrap_or(get_output_filename(&result));
 
-            write_psbqaqc_csv(result, outfile)?;
+            write_psbqaqc_csv(result, outfile, false)?;
         }
         Commands::CheckDB { csvfile } => {
             // TODO: more friendly message (like row number)