Last updated 17 September 2026. Licensor: Interop Solutions Ltd ("we"). By installing or using SMTP-365 ("the Software") you agree to these terms.
On payment of the licence fee we grant you a perpetual, non-exclusive, non-transferable licence to install and use one copy of the Software on one appliance, virtual machine or server for your internal business purposes. Each additional installation requires an additional licence. Licence keys are issued to you and must not be shared or published.
You may evaluate the Software without a licence key for 30 days from first use. After that period the Software holds messages until a valid key is entered. Evaluation use is subject to these terms.
Online purchases are processed by Paddle.com Market Ltd (or Paddle.com Inc. for buyers in the United States) as merchant of record: Paddle is the seller of the licence to you, issues the receipt and VAT invoice, and handles refunds under our refund policy and Paddle's buyer terms. Licence keys are issued and supported by Interop Solutions Ltd under these terms.
A monthly subscription licenses the Software for as long as the subscription is paid; it is not a perpetual licence. If a subscription is cancelled, or the payment a licence key was issued for (a licence purchase, or the first payment of a subscription) is fully refunded or charged back, we revoke the licence key concerned. A refund of a later subscription payment or of a maintenance renewal does not revoke a key by itself; we review it and may revoke the key. An installation with internet access checks its key with our licence server when its relay service starts and about once a day; once it learns that its key has been revoked it holds incoming messages, without deleting them, until a valid key is entered. A partial refund does not revoke a key.
Each licence includes 12 months of maintenance from the date of issue: access to updates and new versions released during that period, and email support. After maintenance ends the Software continues to function indefinitely, but updates released after the maintenance date are not available unless maintenance is renewed. Maintenance may be renewed for further 12-month periods at the renewal fee published on our website at the time (currently £39 per licence per year). The founder price applies to the initial licence purchase only.
You must not copy the Software except for backup, modify, reverse engineer, decompile or disassemble it (except to the extent expressly permitted by law), remove or circumvent licence enforcement, rent, lease, sublicense or resell it, or use it to provide a service to third parties without a partner agreement with us.
The Software connects to Microsoft 365 under your tenant using an application identity you authorise. You are responsible for your Microsoft 365 configuration and for complying with Microsoft's terms. The Software includes open-source components under their own licences; the principal components are listed in the Technical Specification (runtime dependencies), the appliance also contains the components those depend on and the Debian operating system, and a full list and the licence texts are available on request from helpdesk@smtp-365.com.
The Software processes your messages on your own systems. We do not receive their content. Our handling of licence and support data is described in the privacy notice.
We warrant that for 90 days from purchase the Software will perform substantially as described in its documentation. Your remedy for breach of this warranty is, at our option, correction of the fault or a refund of the licence fee. Otherwise the Software is provided "as is" and, to the fullest extent permitted by law, we exclude all other warranties, express or implied, including fitness for a particular purpose.
Nothing in these terms limits liability for death or personal injury caused by negligence, fraud, or anything else that cannot be limited by law. Subject to that, we are not liable for indirect or consequential loss, loss of profit, data or business, and our total liability arising from the Software is limited to the licence fee you paid for it in the 12 months before the claim.
The licence continues until terminated. We may terminate it if you materially breach these terms and do not remedy the breach within 30 days of notice. On termination you must stop using the Software and delete all copies.
These terms are governed by the laws of England and Wales and the courts of England and Wales have exclusive jurisdiction. If any provision is unenforceable the rest remains in effect. These terms are the entire agreement between us regarding the Software.
Questions: hello@smtp-365.com