Multiple Projects

You can open several TIA Portal instances in parallel, across TIA Portal versions V15…V21 and including several of the same version. There is no limit on how many projects you keep open. Each open instance runs its own isolated TIA Portal session, so a crash in one does not affect the others. One instance is active at a time; the Project Explorer and the rest of the workspace always reflect the active instance, and you switch the active instance from the project name at the top of the Project Explorer or from the status bar.

Switching projects from the Project Explorer header

As soon as a TIA Portal is connected or a project is open offline, the Project Explorer header shows the active project's name as a button with an up/down arrow symbol at its end. A TIA Portal that is attached without an open project appears as TIA Portal with its version, for example TIA Portal V20; a project open offline shows its name followed by Offline. Hover over the button to see the active project with its TIA Portal version; a long name that is shortened in the header appears in full there.

Click the name to open its menu. It lists every connected project, the active one marked with a check. Pick a different project and the Project Explorer switches to it immediately. A project whose contents are still being read is marked (loading…) in the list: you can switch to it anyway, the Project Explorer then shows a loading indicator until its tree is ready.

Below the project list, the same menu connects more projects or starts new ones:

• Attach to Running TIA Portal
• Open TIA Project
• Open TIA Project (Offline)
• New TIA Project
• Open Multi-User Session, Upload Project to Multi-User Server and Manage Multi-User Servers (Multi-User needs the Pro plan or above, see Multi-User Session)

While a project is open offline, the menu lists that project first (checked), followed by every connected TIA Portal project. Picking one of those switches to it and closes the offline project. Below the list you find Open TIA Project (Offline) to open a different project offline, and Close Offline TIA Project.

The menu also works from the keyboard: press Tab until the project name has focus, then Enter, Space, Down Arrow or Alt+Down Arrow to open it, and Esc to close it again. The arrow at the far left of the header still folds and unfolds the view; clicking the project name never folds it.

With nothing connected and no project open offline, the header simply reads "Project Explorer" and clicking it folds the view as usual. To connect, click Connect in the empty Project Explorer.

Switching instances from the status bar

The TIA entry at the left of the status bar (very bottom of the window) shows the active instance — the TIA Portal version and project name, with a trailing count such as (3) when more than one instance is open.

When more than one instance is open, click that status-bar entry to open the instance switcher — a picker that lists every open instance (the active one marked with a check) plus an Open / Attach New Instance entry. Selecting an instance makes it active and reloads the Project Explorer for that instance's project.

The Project Explorer always shows the active instance's project. Tree expansion, scroll position and selection are kept per instance — switching back to a previously-active instance restores the tree exactly as you left it.

Opening another instance

The most direct way is the project name at the top of the Project Explorer: click it and choose Attach to Running TIA Portal or Open TIA Project.

Alternatively, open another instance the same way you make the first connection: run Connect, then choose Attach to Running Instance or Open TIA Project. You can also click the Open / Attach New Instance entry in the status-bar instance switcher. All paths lead to the same choice:

Switching projects

Pick a different project from the menu of the project name at the top of the Project Explorer, or from the status-bar switcher, to change the active project. The Project Explorer swaps to the new project's PLCs and blocks, and views that follow the connected project reload for the newly active instance. While the new project's tree is being read, the Project Explorer shows a loading indicator. PLCSim, the Password Vault and other application-wide surfaces stay unchanged across the switch.

The Agents window offers the same switch from the top of its Project Explorer panel — the choice is shared, so switching in either window switches both.

Closing and saving an instance

Run these from the Command Palette (Ctrl+Shift+P); Save Project is also a button in the Project Explorer view title.

Same-version multi-instance

You can open and attach to several TIA Portal projects of the same major version in parallel, each in its own isolated TIA Portal session. There is no limit on the total number of open instances.

Connect will only refuse the action in two specific cases:

• The selected project file is already open in another instance — Connect reports that the project file is already open. Switch to the existing instance from the status bar instead.
• You picked an already-attached running TIA Portal instance from the Attach list — Connect reports that the TIA Portal instance is already attached. The same message also appears if you open a project from file (which starts a fresh TIA Portal) and then later select that same TIA Portal from the Attach list — both entry points share a single instance-per-session rule. Pick a different running instance, or switch to the existing one.

A closed or crashed TIA Portal

If the TIA Portal behind an open instance is closed or ends unexpectedly (window closed, crash, process kill, out-of-memory), Studio notices right away: the instance disappears, a notification names the disconnected project, and the status bar switches to the surviving active instance. Other open instances keep running normally — only the affected session is gone. Run Connect to reconnect at any time.

The notification carries a Reconnect button that opens the same connect choices, so you do not have to look for the command first. If TIA Portal goes away while Studio is reading or writing, the message says what was interrupted, down to the screen it was working on. A screen that could not be loaded because the connection went away says so in the editor and offers Reconnect as well.