# Microsoft Outlook

Application: Microsoft Corporation

Dem still dey call am outlook, classic outlook, outlook.exe

Microsoft Corporation, Productivity

Classic desktop mail and calendar from Office and Microsoft 365. The process na OUTLOOK.EXE. New Outlook na olk.exe. Windows Mail na HxOutlook.exe.

## Wetin you need know

Classic Outlook na OUTLOOK.EXE. New Outlook and Windows Mail na other clients.

This article na about the Win32 Outlook where dey store profiles, OST/PST files, and COM add-ins. Microsoft 365 na the suite where dey often install am. The New Outlook toggle dey start different executable.

- **Wetin e be?**: Classic desktop Outlook

  **Same thing as New Outlook?**: No. That client na olk.exe

  **Same thing as Windows Mail?**: No. Mail na HxOutlook.exe

Feex tok say

If mail "move" after Windows 11 prompt, I go check whether you still dey on OUTLOOK.EXE or you don already dey on olk.exe. Dem no be the same client, and Windows Mail na third one.

## Wetin be Microsoft Outlook?

Classic Microsoft Outlook na the desktop mail and calendar app where im image name na OUTLOOK.EXE. E be part of Microsoft 365 Apps or older Office. E no be New Outlook (olk.exe) and e no be Windows Mail (HxOutlook.exe).

## If you never use am before

If your work mailbox don dey live inside Outlook for years, na classic desktop client usually be this: ribbon, profiles, and OST cache. E no be the Microsoft 365 suite page, e no be the New Outlook Store app, and e no be the Windows 10 Mail tile. Install am with Office or Microsoft 365. The "Try the new Outlook" switch dey leave this exe and start olk.exe.

## Wetin dem dey use am for?

**Mail and calendar**

Exchange, Microsoft 365, and many IMAP accounts inside one Win32 window.

**OST, PST, and profiles**

Offline cache and personal folders. New Outlook no dey treat PST the same way.

**COM add-ins**

Classic Outlook dey load COM and VBA add-ins. olk.exe no dey host that model.

## Na who e dey for?

- Work PCs where still need classic Outlook add-ins
- People where get PST archives where dem must continue to open
- Anybody where Windows 11 dey push toward New Outlook

## Current status

Dey actively develop am, as Microsoft dey push plenty consumers go New Outlook. Classic Outlook still remain di Win32 client for Microsoft 365 Apps.

## How old e be?

Outlook 97 launch for 1997 and replace Exchange Client and Schedule+ for plenty offices. E no be Windows Messaging from Windows 95, and e no be di 2022 New Outlook package.

## Versions

Major channels first. Exact build numbers no dey all verified here.

Classic Outlook (OUTLOOK.EXE)

New Outlook (olk.exe)

Outlook on di web

## System requirements

Values dey follow wetin di publisher release publicly. Workload still dey change di real need.

### Minimum

| CPU              | 1.6 GHz or faster, 2-core, per Microsoft for Microsoft 365 Apps               |
| ---------------- | ----------------------------------------------------------------------------- |
| RAM              | 4 GB for 64-bit, according to Microsoft. Large mailbox cache go need pass dat |
| Operating system | Current Windows release Microsoft list for Microsoft 365 Apps                 |
| Other            | Some Outlook features need Microsoft Edge WebView2, according to Microsoft    |

## Resource profile

- **CPU demand**: Indexing, add-ins, and huge inbox

  **RAM demand**: Fit remain big after full workday of mail

  **Disk demand**: OST growth under AppData

  **Network demand**: Exchange / Microsoft 365 sync

## Installed processes

Dese executables belong to dis product when e dey installed.

| OUTLOOK.EXE | Classic desktop Outlook |
| ----------- | ----------------------- |

## Startup components

Classic Outlook fit start with Windows from im own option or shortcut. Dat one no be New Outlook and e no be di Mail app.

## File locations

| Typical Click-to-Run | C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE |
| -------------------- | ----------------------------------------------------------- |
| OST / PST            | C:\Users\\\<you>\AppData\Local\Microsoft\Outlook\\          |

## File formats

MSG, PST, OST, ICS, EML

## Common wahala dem

### Di New Outlook toggle dey hide dis client

Off "Try the new Outlook" if you still need PST or COM add-ins. olk.exe na different app.

### Add-ins dey make Outlook show Not Responding

outlook.exe /safe na di classic add-in test. E no dey start New Outlook.

## How to get unstuck

### Check which Outlook you launch

Open file location. Office16\OUTLOOK.EXE na dis article. olk.exe na New Outlook. HxOutlook.exe na Windows Mail.

### Start classic Outlook for Safe Mode

outlook.exe /safe dey skip COM add-ins. scanpst.exe na di inbox repair tool for dis client, no be for olk.exe.

### Repair Microsoft 365 Apps if classic Outlook dey miss

No download outlook.exe from phishing zip. Work mail need di tenant admin if activation fail.

## Alternatives

New Outlook, Outlook on the web, Thunderbird, and Windows Mail dey overlap to read mail. Dem no get di same PST and COM add-in tori.

## Official help and downloads

Start with di vendor. Random exe sites no be support channel.

| Product page            | [www.microsoft.com/microsoft-365/outlook ](https://www.microsoft.com/microsoft-365/outlook)Wetin Microsoft dey release as Outlook                                                                                                                                                                    |
| ----------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Outlook help            | [support.microsoft.com/outlook ](https://support.microsoft.com/outlook)Help for profiles, sync, and crash                                                                                                                                                                                            |
| Classic vs new features | [support.microsoft.com/office/feature-comparison-between-new-outlook-and-classic-outlook-de453583-1e76-48bf-975a-2e9cd2ee16dd ](https://support.microsoft.com/office/feature-comparison-between-new-outlook-and-classic-outlook-de453583-1e76-48bf-975a-2e9cd2ee16dd)Wetin you go lose if you switch |
| Command-line switches   | [support.microsoft.com/office/command-line-switches-for-microsoft-office-products-079164cd-4ef5-4178-b235-441737deb3a6 ](https://support.microsoft.com/office/command-line-switches-for-microsoft-office-products-079164cd-4ef5-4178-b235-441737deb3a6)outlook.exe versus olk.exe                    |
| Requirements hub        | [www.microsoft.com/microsoft-365/microsoft-365-and-office-resources ](https://www.microsoft.com/microsoft-365/microsoft-365-and-office-resources)CPU, RAM, and OS Microsoft list                                                                                                                     |

## Related hardware

Large OST go need SSD and enough RAM make classic Outlook no go dey page. GPU no dey speed up inbox sync.

## Technical details

Technical details

Classic Outlook builds dey follow di Microsoft 365 channel. Dis article no pin any build.

## Related

Dis entities connect to dis article. Type dey show for every link.

[OUTLOOK.EXE: Application Process](https://feex.it/wiki/l/pcm/process/outlook.exe/)[New Outlook: Application](https://feex.it/wiki/l/pcm/software/new-outlook/)[Windows Mail: Application](https://feex.it/wiki/l/pcm/software/windows-mail/)

## Sources and verification

Recorded source label: August 2026. Dis label no establish independent verification. [How we dey do research](https://feex.it/wiki/research/).

- [Microsoft Outlook product page ](https://www.microsoft.com/microsoft-365/outlook)· Official Outlook product
- [Microsoft Support: Outlook ](https://support.microsoft.com/outlook)· Help for profiles, add-ins, and OST
- [Feature comparison: new vs classic Outlook ](https://support.microsoft.com/office/feature-comparison-between-new-outlook-and-classic-outlook-de453583-1e76-48bf-975a-2e9cd2ee16dd)· Wetin each client fit do
- [Foxhole process map ](https://foxhole.feex.it/)· First-party samples on top Windows PCs. No be lab benchmark.

## Dis article make sense to you?

Yes or no dey enough. Choose reason if you want, or add short note.

Quick facts

The short identity of dis page. Specs, sources, and the full story still dey inside the article.

- **Developer**: Microsoft Corporation

  **Category**: Mail and calendar

  **Process**: [OUTLOOK.EXE](https://feex.it/wiki/l/pcm/process/outlook.exe/)

  **License**: Microsoft 365 subscription or perpetual Office / Outlook SKU

  **First released**: 1997

  **Official site**: [microsoft.com/microsoft-365/outlook](https://www.microsoft.com/microsoft-365/outlook)

  **Feex map am**: Dem see am on top Windows PCs for Foxhole

Recorded source status: Feex Reviewed: Recorded source label: August 2026. Dis label no establish independent verification.

---

Source: [Canonical Feex Wiki page](https://feex.it/wiki/l/pcm/software/microsoft-outlook/)

[Developer guide](https://feex.it/wiki/developers/) | [API policy](https://feex.it/developers/api-policy/) | [Agent guidance](https://feex.it/wiki/llms.txt)