> For the complete documentation index, see [llms.txt](https://wiki.inels.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.inels.com/inels-bus/inels-design-manager-idm3/opening-older-idm3-projects.md).

# Opening older projects

*Part 3 — Reference.*

***

## 28.1 What happens

Open a project made in an older version of iDM3 and you are told:

> *"This project was created in an old version of the IDM application and must be converted to work properly."*

The **Project conversion** dialog then walks you through it.

***

## 28.2 The conversion needs the central unit

The dialog is explicit:

> *"IDM needs to be connected to CU in order to convert the project."*

This surprises people. Conversion is not a purely local file operation — iDM3 reads the actual unit structure from the installation to work out how old objects map to new ones.

**So you cannot convert an old project at your desk without the installation.** Plan for it: do conversions on site, or with a remote connection to the CU.

***

## 28.3 The dialog

| Field                      | Meaning                              |
| -------------------------- | ------------------------------------ |
| **Project IDM version:**   | The version that created the project |
| **Current version:**       | The version you are running          |
| **IP address : port**      | The CU to connect to                 |
| **CU unit type : address** | Which central unit                   |
| **Select unit**            | Choose the CU                        |

| Button                          | What it does                  |
| ------------------------------- | ----------------------------- |
| **Select**                      | Confirm the chosen unit       |
| **Connect and Convert**         | Connect to the CU and convert |
| **Continue without conversion** | Open the project unconverted  |
| **Back**                        | Return to the previous step   |
| **Repeat scan**                 | Scan the structure again      |
| **Convert units**               | Convert the units             |

If the connection fails you will see:

> *"Cannot connect to the specified CU. Please check the entered data"*

On success:

> *"Project was succesfuly converted"* — under the title **Conversion success**.

*(The spelling is as it appears on screen.)*

> **"Continue without conversion" is not a fix.** The project opens, but old objects may not behave correctly and you may not find out until something fails on site. Use it to *inspect* a project, not to work on one.

***

## 28.4 Unavailable units

A separate view, **Unavailable units**, lists units in the project that this version does not support — typically discontinued hardware.

| Control                  | What it does                                   |
| ------------------------ | ---------------------------------------------- |
| **Converted units:**     | What has been converted so far                 |
| **Hide converted units** | Filters the list to what still needs attention |

Where a modern equivalent exists, conversion maps the old unit onto it. Where none exists, the unit must be replaced — in the project, and usually in the building too.

***

## 28.5 Related warnings

| Message                                            | Meaning                                                            |
| -------------------------------------------------- | ------------------------------------------------------------------ |
| *"Not remapped devices detected"*                  | Some devices were not mapped — check them before uploading         |
| *"Please remap device or change/remove its links"* | A device needs remapping; use **ReMap unit** in the Device manager |
| *"Module type \[0x…] is not supported."*           | That module type does not exist in this version                    |
| *"Unable to delete this object because is i use!"* | Something still references it *(spelling as shown)*                |

**ReMap unit** is the tool for all of these — see [Chapter 16 §16.6](/inels-bus/inels-design-manager-idm3/idm3-device-manager-reference.md#remap-unit). It moves every wire, group and condition from the old device to the new one. Deleting and re-adding silently destroys the wires.

***

## 28.6 A safe conversion procedure

| #  | Step                                                                                   |
| -- | -------------------------------------------------------------------------------------- |
| 1  | **Copy the original `.elp` somewhere safe.** Conversion is not reversible.             |
| 2  | Download what the CU is currently running (`Load from central unit`) and save that too |
| 3  | Read `Change log.txt` for the versions in between                                      |
| 4  | Connect to the CU and run **Connect and Convert**                                      |
| 5  | Work through **Unavailable units** and resolve every one                               |
| 6  | Check for *"Not remapped devices detected"* and use **ReMap unit**                     |
| 7  | Open the **Wire manager** and confirm the wire count matches what you expected         |
| 8  | Check **Prefernces** for anything that now exceeds a limit                             |
| 9  | Test in **Simulation** before uploading                                                |
| 10 | Upload, then verify against the building                                               |

Step 1 is not optional. Step 7 catches the most common conversion damage: wires quietly lost with an unsupported device.

***

**Next:** [Chapter 29 — Commissioning checklist](/inels-bus/inels-design-manager-idm3/idm3-commissioning-checklist.md).