Download and install the latest version of Filestar.
Right click on one or more Ost file(s) on your desktop and select Convert with Filestar.
Type convert to mhtml in the search box.
Press Convert.
Or let an AI agent do it: filestarcli -i file.ost -c "convert to mhtml" (how).
Documents - File Explorer─☐✕
This PC › Documents
Home
Desktop
Downloads
Documents
Pictures
Music
.ostContract.ost
.xlsxBudget.xlsx
.pdfReport.pdf
.pngLogo.png
Filestar*Help✕
Drop files here to get started
ConvertMergeCompressExtractMoveZip
Let your AI agent convert OST to MHTML
Claude Code, Codex, Cursor and other agents can do this on your computer with Filestar. Your files stay on your machine.
Install Filestar and add it to your agents:
npm install -g filestar
filestarcli agent install
Then ask your agent:
“Convert the OST files in my Downloads folder to MHTML”
Or run it yourself:
filestarcli -i file.ost -c "convert to mhtml"
Runs on your computer, so your files stay on it. Works on Windows, macOS and Linux. 50 free conversions with the npm install, no account needed.
Can my AI agent convert OST to MHTML?
Yes. Install the Filestar CLI with npm install -g filestar and your agent can run filestarcli -i file.ost -c "convert to mhtml" on your computer, so your files stay on it.
n OST file is a data file created by Microsoft Outlook (2005 or later), an email client and personal information manager. It is used to store a copy of mailbox information from an Office 365, Exchange, or Outlook.com account. OST files may contain email messages, contacts, tasks, calendar data, and other account information.
MHTML, short for MIME HTML, is a file format that archives web pages. The format combines HTML code, images, JavaScript, and other resources into a single file using MIME type multipart/related. This method of encapsulating a complete webpage (or set of webpages) in a single file makes MHTML files convenient for saving, sharing, and viewing web content offline. MHTML files typically have the extension .mhtml or .mht and can be opened by various web browsers.
