Resolve Windows Installer error 1618: another installation is running
What to do first
Resolve Windows Installer error 1618: another installation is running. Windows Update, another setup, or a pending-restart msiexec transaction may already be running. Record the current state before changing it, use only the supported Windows path described below, and verify the same operation again after any required restart.
This is a general troubleshooting guide, not an announcement of a current outage.
Affected products and symptoms
- Product
- Windows Installer
- Versions and conditions
- Windows 11 (confirm the edition and hardware requirements for the feature)
- Error codes and identifiers
- 1618
Symptoms
- Resolve Windows Installer error 1618: another installation is running.
- The same condition can persist after a retry or restart.
Causes and conditions
Windows Update, another setup, or a pending-restart msiexec transaction may already be running.
Before you start
- Save open documents and allow time for a Windows restart if required.
- Run administrative actions only on a personally managed PC or with administrator approval.
- Save the diagnostic command output so the before and after states can be compared.
Precautions
- Do not bulk-delete registry entries, system folders, credentials, or storage metadata.
- Do not run unofficial scripts or unknown drivers with administrator rights.
Tools and official pages used in this guide
Check the official requirements, interface names, and limitations for this step.
Step-by-step instructions
Check open setup windows and Settings > Windows Update. The presence of an msiexec process alone does not mean it is stuck. Let active work finish and avoid starting another installer on top of it.
Check the taskbar and notification area for Windows Update, Microsoft Store, Office update, or another setup.exe. Do not terminate an installer with moving progress; wait, then restart if requested.
Error 1618 indicates another installation is running. A missing desktop setup window does not rule out Windows Update or managed deployment. A visible msiexec.exe process alone does not establish that termination is safe. Record start time, concurrent setups and update notices to identify whether the owner is the user or administrator.
At the time of error 1618, check Windows Update, organization deployment tools and other setup windows. A visible msiexec.exe process does not establish that terminating it is safe. Wait for an installation showing progress and avoid launching duplicate copies of the original setup.
Close open installer windows and check Windows Update progress and any pending restart. An msiexec process alone does not prove that installation is stuck.
This command launches the MSI; it is not read-only. Check the exit result and log, and on failure share the area around Return value 3 after removing personal data.
Wait for an operation showing progress; apparent inactivity alone does not justify killing it. Complete requested restarts after saving work and avoid managed deployment windows. Give administrators the error time if deployment history is unavailable. Do not open repeated copies of the same setup.
Get-Process msiexec -ErrorAction SilentlyContinueAllow the active installation to finish normally. If Windows requests a restart, restart, then launch only the one target MSI.
This command launches the MSI; it is not read-only. Check the exit result and log, and on failure share the area around Return value 3 after removing personal data.
Retry once after the other operation completes. Save MSI identity, publisher, start/end time and exit code. Use the real MSI path and writable log destination; logging commands still perform installation. For EXE setup, use publisher-specific logging instead of assuming every installer can be replaced with msiexec.
Get-Process msiexec -ErrorAction SilentlyContinueOfficial links for this step
- MsiExec.exe and InstMsi.exe error messages
Check the official requirements, interface names, and limitations for this step.
- MsiExec.exe and InstMsi.exe error messages
If a restart is requested, save your work and restart, then run just one target MSI. The logging command starts a real installation; it is not a read-only status command. Replace C:\path\package.msi with your legitimate local MSI and check the log destination before running it.
After the other operation finishes, run the intended setup once and record start time and exit code. Perform a requested restart first after saving work. If 1618 persists, check deployment history around that time instead of disrupting pending updates by stopping services.
This is an installation command for PowerShell. Replace the MSI path before running it and check the completion screen. If it fails, inspect package-install.log in your temporary folder and remove personal information before sharing the log with support.
This command launches the MSI; it is not read-only. Check the exit result and log, and on failure share the area around Return value 3 after removing personal data.
Separate a new product error from the resolved installation conflict. Verify application startup and the needed function. For recurrence, compare update/deployment state at the same time and ask for a suitable window. Avoid mass msiexec termination or permanently disabling Installer. Provide concurrent-operation completion, restart and retry results with the correct product logs.
msiexec /i "C:\path\package.msi" /L*v "$env:TEMP\package-install.log"
Check the result
- The intended installer completes and the installed application launches
- The verification command reports the expected enabled, healthy, or connected state.
- The result remains correct after a Windows restart and no new matching critical event appears.
If the problem continues
- For continuing managed deployments, ask the administrator for an installation window
- If hardware requirements, organization policy, or server settings are responsible, ask the owner to make the change instead of bypassing it on the client.
Scope of this guide
Troubleshooting guide — Restore the feature so it starts, connects, or completes normally and passes the same verification after a Windows restart.
Frequently asked questions
Should I force-end msiexec in Task Manager?
Avoid it because it can damage installation state. Let setup finish normally and wait for Windows Update or a requested restart.
Does 1618 mean the package is corrupt?
It primarily indicates concurrent installation. Capture a verbose log only if it recurs with one installer running.
May I terminate msiexec.exe simply because it is still present?
The process name alone does not show ownership or progress. Check Windows Update, deployment tools and the launched setup. For managed deployments, give the administrator the time and identify affected installations before acting.
Official sources and dates
Source publication or resolution date: Not specified. Sources checked: 2026-10-13. The check date is not the date the problem first occurred. Interface labels can vary between versions and display languages.
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