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What is CsvMail Sender?

What is CsvMail Sender?

A CSV-based personalized email sender for Windows

CsvMail Sender is a Windows Forms app for creating and sending personalized emails from CSV data.

It loads one CSV file or a folder of CSV files, replaces template tags with values from each row, lets you preview the generated messages, checks for common problems before sending, and sends selected rows through SMTP.

The app is published as free and open source software on GitHub.

GitHub:
https://github.com/StayHomeLabNet/CsvMail-Sender

Download:
https://github.com/StayHomeLabNet/CsvMail-Sender/releases/

User manual:
https://github.com/StayHomeLabNet/CsvMail-Sender/blob/main/docs/user-manual.en.md

When is CsvMail Sender useful?

1. Sending personalized notices from a CSV list

Many small business tasks start with a simple CSV file.

For example:

customer notices
membership renewal reminders
event announcements
school or community messages
internal company notifications
invoice or payment reminders
service expiration notices

CsvMail Sender lets you use CSV columns such as Name, Company, Plan, or Expiration Date inside the email subject and body.

Example:

Dear [[Name]],

Your current plan is [[Plan]].
The expiration date is [[Expiration Date]].

Each row is turned into a separate message, so the email can feel personal without manually editing every message.

2. Checking emails before sending

Bulk email mistakes can be stressful.

CsvMail Sender includes preview and preflight tools so you can check the contents before sending.

You can confirm:

whether the correct recipient address is used
whether template tags are replaced correctly
whether required fields are missing
whether attachments exist
whether there are duplicate addresses
whether many emails are going to the same domain

This is useful when you want to avoid sending an unfinished template, a missing attachment, or an email to the wrong address.

3. Creating emails with templates

CsvMail Sender supports reusable templates.

You can create an email body once, then use it again with different CSV files.

It supports simple tags such as:

[[Name]]
[[Company]]
[[Plan]]

It also supports conditional template blocks such as:

[[if:Company]]
[[Name]], [[Title]] at [[Company]]
[[else]]
[[Name]], [[Title]]
[[endif]]

This makes it possible to change part of the email depending on whether a CSV field has a value.

4. Sending test emails before the real send

Before sending to all recipients, you can preview the generated message and send a test email.

This is especially useful when checking:

subject line
line breaks
inserted CSV values
HTML formatting
attachments
sender name
SMTP settings

Instead of sending immediately to everyone, you can test first and reduce the risk of mistakes.

5. Using CC, BCC, and attachments from CSV data

CsvMail Sender can use fixed CC/BCC values or read CC/BCC values from CSV columns.

It can also attach common files or per-row attachments based on a CSV column.

This is useful when each recipient needs a different file, such as:

a report
a certificate
a statement
an invoice
a personalized document

6. Managing SMTP settings

CsvMail Sender sends mail through SMTP.

You can manage multiple SMTP profiles and test SMTP sending from the app.

Important SMTP fields include:

host
port
encryption
user name
password
from address
from name
test recipient

SMTP passwords are stored locally and are not included when exporting settings.

7. Sending slowly and safely

When sending many emails, sending too quickly can cause problems depending on the mail provider.

CsvMail Sender includes controls such as:

interval between messages
per-minute limit
same-domain wait
scheduled sending

This helps reduce sending pressure and makes delivery easier to manage.

8. Keeping records after sending

After sending, CsvMail Sender can keep send history and logs.

You can review results, retry failed rows, export results, and open logs.

This is helpful when you need to confirm:

which rows were sent
which rows failed
what error happened
when the send was completed
whether a retry is needed

Main features

Load a single CSV file or a folder of CSV files
Detect common encodings, including UTF-8, UTF-8 with BOM, and Shift-JIS CP932
Preview CSV data and generated emails before sending
Use template tags such as [[Name]] and [[Plan]]
Use conditional template blocks
Insert tags from available CSV columns
Use fixed CC/BCC or CC/BCC columns from the CSV
Attach common files or per-row files
Send text or HTML email
Run preflight checks before sending
Export dry-run reports as CSV or HTML
Review a final send summary before sending
Manage multiple SMTP profiles
Control send speed
Schedule sending for a future time
Review send history and retry failed rows
Keep template backups, compare versions, and restore old templates
Switch between English and Japanese UI
Switch between Basic and Advanced UI modes
Export and import settings

Cases where it may not be the best fit

CsvMail Sender is not mainly designed for:

marketing automation with tracking pixels and campaign analytics
newsletter design with drag-and-drop layouts
cloud-based team collaboration
very large-scale email marketing
sending without an SMTP account
replacing a professional mailing list service
bypassing mail provider sending limits

It is best suited for controlled, practical, CSV-based email sending from a Windows environment.

Safety notes

Before sending real emails, it is recommended to:

check the CSV preview
check the mail preview
run the preflight check
send a test email
confirm SMTP settings
review the final send summary
start with a small test CSV if the data is important

CSV files with duplicate headers are rejected so ambiguous row values cannot be sent silently.

For larger sends, configure the sending interval, per-minute limit, and same-domain wait according to your SMTP provider’s rules.

SMTP provider limits and authentication requirements vary by environment.

Quick start

Open Settings > SMTP Settings.
Configure your SMTP profile.
Click Browse to load one CSV file, or Browse Folder to load multiple CSV files.
Select the recipient column in Email Column.
Open the template editor.
Create or select an email template.
Insert CSV tags into the subject or body, such as [[Name]].
Click CSV Preview to check the source data.
Click Mail Preview to check the generated emails.
Click Preflight Check to catch problems before sending.
Send one test row.
Click Start Send and review the final send summary.

In one sentence

CsvMail Sender is a practical Windows tool for turning CSV rows into personalized emails, checking them before sending, and delivering them through SMTP with logs and safety checks.

It is especially useful when you want to send CSV-based notices, reminders, announcements, or per-recipient messages without manually writing each email.