Windows · medium · Applications & Microsoft 365

Office applications open slowly, hang, or start with a blank window

Almost always an add-in, a mapped network path, or a printer driver — not Office itself.

What you see

Word or Excel takes a minute to open, hangs on start, or shows a white rectangle before drawing. Files from a network share are worst.

What is actually wrong

Add-ins load before the window is drawn, so a slow or broken one delays everything. Office also queries the default printer at startup, so an unreachable network printer produces exactly this. A slow or disconnected mapped drive in the recent files list does the same.

Codes and articles

Excel not respondingWord not respondingsafe mode office0xc0000005 excel

Fixes (3)

Bisect the add-ins

The application itself30 minuteslow riskreversible

Safe mode is fast. That result tells you it is an add-in with near certainty.

List what is loaded and how long each took — Office records this itself.

PowerShell

Get-ItemProperty 'HKCU:\Software\Microsoft\Office\16.0\Excel\Resiliency\StartupItems' -ErrorAction SilentlyContinue

In the application: File → Options → Add-ins. Manage COM Add-ins → Go, and disable them all.
Restart normally, confirm it is fast, then re-enable them one at a time, restarting between each.
Disabling them all and leaving it there works but tells you nothing, and someone will re-enable the culprit in a month. Twenty minutes of bisecting names it permanently.
Adobe, antivirus and PDF-maker add-ins are the usual culprits, and the vendor usually has a current version that behaves.
Check the Disabled Items list too, which Office maintains separately: File → Options → Add-ins → Manage: Disabled Items.

Confirm it workedThe application opens in a few seconds with the add-ins you need enabled.

If you need to undo itEvery add-in can be re-enabled in the same dialog.

Remove the startup dependencies outside Office

Elevated PowerShell25 minuteslow riskreversible

Safe mode is also slow. The delay is something Office is waiting for, not something it is loading.

Set the default printer to Microsoft Print to PDF temporarily and test.
PowerShell
```
Get-CimInstance Win32_Printer | Where-Object Default -eq $true | Format-List Name,PortName,WorkOffline
```
Office queries the default printer's capabilities when it starts. If that printer is on a server that is off or unreachable, the query blocks until it times out — typically thirty to sixty seconds, exactly the delay being described.
Check for disconnected mapped drives, which have the same effect via the recent files list.
Command Prompt
```
Get-PSDrive -PSProvider FileSystem | Format-Table Name,Root,Used,Freenet use
```
Clear the recent documents list if it references a share that no longer exists.
PowerShell
```
Remove-Item "$env:APPDATA\Microsoft\Office\Recent\*" -Force -ErrorAction SilentlyContinue
```
Check the default save location under File → Options → Save. A default set to an unreachable share delays every open and save.

Confirm it workedThe application opens in a few seconds with the correct default printer restored.

If you need to undo itSet the default printer back and re-map any drives that are still needed.

Run the online repair

Settings → Apps45 minuteslow riskreversible

Nothing above accounts for it.

Settings → Apps → Installed apps → Microsoft 365 → Modify → Quick Repair first. It takes a few minutes and needs no network.
If that does not resolve it, run Online Repair, which reinstalls the whole product from Microsoft.
Online Repair is effectively a reinstall that preserves settings and licence state. It takes half an hour and a good connection, and it resolves the file-level damage that Quick Repair cannot.
Confirm the update channel is the one intended — a machine on a preview channel can carry a defect that the monthly channel does not.
PowerShell
```
Get-ItemProperty 'HKLM:\SOFTWARE\Microsoft\Office\ClickToRun\Configuration' | Format-List CDNBaseUrl,VersionToReport,UpdateChannel
```
Update to the current build of that channel after the repair.

Confirm it workedThe applications open promptly and the version reported matches the intended channel.

If you need to undo itA repair does not remove documents or settings. The Office deployment tool can roll back to a previous build if a specific version was better.

Where this stops. This write-up was written and checked by hand. It says what each step changes, how to confirm it worked and how to reverse it, and anything destructive is flagged before you reach it. If it does not match what your machine is doing, search the Support Centre for the exact code or message — and when something needs a person, get in touch.