# Migrating from Mesh Java Client to Mesh API **URL:** \ **Category:** Message Exchange for Social Care and Health (MESH)\ **Tags:** onboarding\ **Created:** [19 May 2026 11:17 UTC](https://developer.community.nhs.uk/t/migrating-from-mesh-java-client-to-mesh-api/12201 "2026-05-19T11:17:30Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Medefer\_Developer](https://avatars.discourse-cdn.com/v4/letter/m/a587f6/32.png) [@Medefer\_Developer](https://developer.community.nhs.uk/u/Medefer_Developer)\ **Post date:** [19 May 2026 11:17 UTC](https://developer.community.nhs.uk/t/migrating-from-mesh-java-client-to-mesh-api/12201/1 "2026-05-19T11:17:30Z")
We currently use Mesh Java Client for our integration with Mesh and are looking to move to Mesh API. We already got a Production mailbox setup and working How is onboarding handled when the deploying organisation are not new, but the product is? ---
**Author:** ![paddy.yung](https://avatars.discourse-cdn.com/v4/letter/p/e79b87/32.png) [@paddy.yung](https://developer.community.nhs.uk/u/paddy.yung)\ **Post date:** [19 May 2026 12:47 UTC](https://developer.community.nhs.uk/t/migrating-from-mesh-java-client-to-mesh-api/12201/2 "2026-05-19T12:47:32Z")
Hi, Your MESH mailbox in the Live Production environment is for use with the Java MESH Client only. You may only connect to it with your Medifer MESH product once you have completed MESH API onboarding and have been issued a MESH API Technical Conformance Certificate. You may then request a new mailbox in Production, or if you wish to connect to your existing mailbox, you must do so using a TLS certificate with a subject CN that contains \*.api.mesh-client.nhs.uk which can only be issued upon the production of a MESH API Technical Conformance Certificate as proof of onboarding. Hope that helps Paddy ---
**Author:** ![Medefer\_Developer](https://avatars.discourse-cdn.com/v4/letter/m/a587f6/32.png) [@Medefer\_Developer](https://developer.community.nhs.uk/u/Medefer_Developer)\ **Post date:** [19 May 2026 14:17 UTC](https://developer.community.nhs.uk/t/migrating-from-mesh-java-client-to-mesh-api/12201/3 "2026-05-19T14:17:04Z")
Thanks Paddy. Does that mean for INT environment we need to request a new mailbox and start from there? FYI, we have already added Mesh API product onto our DOS this morning ---
**Author:** ![paddy.yung](https://avatars.discourse-cdn.com/v4/letter/p/e79b87/32.png) [@paddy.yung](https://developer.community.nhs.uk/u/paddy.yung)\ **Post date:** [19 May 2026 14:40 UTC](https://developer.community.nhs.uk/t/migrating-from-mesh-java-client-to-mesh-api/12201/4 "2026-05-19T14:40:03Z")
Testing of your MESH API product will be done in the Path to Live INTEGRATION environment. If you don’t already have any mailboxes in the INT environment, feel free to request them by filling by submitting a [mailbox request form](https://nhsdigitallive.service-now.com/csm?id=sc_cat_item&sys_id=40bdf7281b32b61083b0a7d0b24bcbcd&sysparm_category=aa619d22973fda90dd80f2df9153afce). Or if you have registered your MESH API product in the Digital Onboarding Service, once you have submitted your use case and had it approved, you’ll be sent some instructions on how to request some MESH mailboxes in INT and also details of the conformance tests that will need to be witnessed for technical conformance onboarding. You will also need to log a call to request a TLS certificate. Kind Regards Paddy ---
**Author:** ![Nigel\_Watts](https://avatars.discourse-cdn.com/v4/letter/n/51bf81/32.png) [@Nigel\_Watts](https://developer.community.nhs.uk/u/Nigel_Watts)\ **Post date:** [21 May 2026 08:51 UTC](https://developer.community.nhs.uk/t/migrating-from-mesh-java-client-to-mesh-api/12201/5 "2026-05-21T08:51:22Z")
Your MESH API onboarding will commence when you submit the Use Case section within the Digital Onboarding Service for approval. This will open up the remainder of the sections and will act as the trigger for the next steps in the process.