Troubleshooting steps to fix ‘scanpst.exe fails with Fatal Error 80040818’

Outlook PST powers the smooth functioning of Outlook by acting as a safe-house for all emails, contacts, calendar entries, notes, etc. associated with user mailboxes. However, with time and continued usage, data keeps piling up within PST files pushing them towards size limit breach and eventual corruption. The ScanPST.exe utility offered by Microsoft comes handy to detect and fix errors and corruption within PST files. While it works in most situations, sometimes it can fail due to several reasons and throw cryptic errors like the ‘Fatal Error 80040818’ leaving users confused and clueless as to what should be done next.

Read on to find out everything there is to know about this error and how you can fix it without much trouble.

Causes that trigger ‘Fatal Error 80040818’

Outlook supports PST files of two formats – ANSI and Unicode. Outlook versions 2002 and earlier supported ANSI format PST files which were bound by a 2GB size limit. This limit was extended to 20GB for Unicode format PST files supported by Outlook versions 2003 and beyond. The amount of data that your Outlook PST can handle therefore depends on the format in which it is encoded. Whenever the size of the PST file approaches its limit, it starts facing the threat of corruption.

Other causes of PST file corruption include:

  • Accessing ANSI format PST file with Outlook 2003 or later versions
  • Over-stuffing PST files with data without cleaning or archiving them once a while
  • Abrupt system termination or Frequent Power surges
  • Virus infection to the files
  • Bad sectors on the hard drive where the PST is saved

If your Outlook PST file has been corrupted owing to any of the above mentioned reasons, you are bound to face problems. Resolving them at the earliest is the only way to get back to work.

Solutions to ‘ScanPST.exe fails with fatal error 80040818’

The Inbox Repair utility ScanPST.exe offered by Microsoft is the first method used by most Outlook users to detect and fix corruptions and other errors within PST files. However, in cases of severe PST corruption, this utility fails to perform its task and terminates throwing errors like ScanPST.exe fails with fatal error 80040818. In such cases, you can try out one of the below mentioned techniques to fix the issue:

  • Reinstall MS Outlook – this might fix any anomalies in PST file behavior
  • Use CHKDSK utility available in Windows OS– this will help repair disk permissions and other system errors
  • Split and Compress PST files – this will help in reducing PST file size which is the original cause of PST file corruption
  • Try moving the corrupted file to a system installed with earlier version of Outlook or convert the Outlook PST file from ANSI format to Unicode format

Though these tricks should help you fix the problem, if the error still doesn’t budge, read the next section to find out our pick for the best PST repair software which will empower you to defeat this error for sure.

Sure-shot remedy for PST file corruption

Extensive research across various popular technical forums point out that the best Outlook repair utility available online is Stellar Phoenix Outlook PST Repair. Powered by advanced scanning and repair algorithms, this software can easily detect and repair corruption within PST files and rid it off all nasty errors. The process is non-intrusive and non-destructive so the format of your PST file data isn’t modified in any way during the repair. A simple 3-step approach (Scan-Preview-Save), fully interactive GUI, and tons of other associated benefits make this software the ideal choice to fix problems like Fatal Error: 80040818.

Wrapping it up

Getting on top of PST file corruption is easy when you have inbuilt utilities like ScanPST.exe. However, such utilities fail when severe corruption strikes. Thus, keeping reliable professional software like Stellar Phoenix Outlook PST Repair handy is the best way to handle such errors.


PST Repair Tool to Recover All Outlook Mailbox Items – Free Trial


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PGP Messaging not blocking outgoing emails when ‘encrypt’ is selected

I need a solution

I’ve looked through google and these forums for several hours without a solution.

I have Symantec Encryption Desktop 10.3.2 installed on a Windows 7 Pro 64-bit system running Outlook 2007.

Symantec Encryption Desktop has an Enterprise Complete Edition license.

All security policies in PGP Messaging are set to the default values but when I send an email from Outlook with [PGP] in the subject and ‘Encrypt’ selected, the email is sent unencrypted instead of getting blocked. There is no key for the recipient in my keychain.

SSL is disabled in Outlook.

The server type is set to ‘Internet Mail’, but I have tried with ‘MAPI/Exchange’ with the same result.

Proxy options in SED are set to ‘Automatic’.

Microsoft Security Essentials are installed on the system but real-time protection is disabled currently.

Looking through the logs, I’ve found the line “Outlook Plugin: User encrypted a message with subject [PGP] test8”, this is however not true since it is sent unencrypted.

I’ve included a debug log.

Any help with this would be greatly appreciated.



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Exchange OST to PST Converter

I do not need a solution (just sharing information)

Download Free Exchange OST to PST Conversion Software and easily recover corrupted OST data and convert into Outlook PST format with all Emails, Send Items, Contacts, calendar, Notes, entries, and journals. It has complete solution to import OST files into PST with all emails item. It gives you authority to see preview of their recovered OST files before conversion and convert them into new readable PST files without facing any problems. If you want to restore recover OST file in to Exchange Server and office 365. Download free version software and connect the Exchange server Or Office 365. With the help of this software users can smartly recover their corrupt OST file and successfully convert OST data into PST formats with other format like MSG, EML, EMLX, MBOX, HTML, vCard, and vCal file.
It extremely split large PST file form small PST and provides free demo facility in which you can repair 30 emails per folder into each formats. It can easily convert your lost, damaged or corrupt OST files data such as inbox, outbox, sent items, draft and deleted items etc.
The program is compatible with all versions of MS Outlook 2016, 2013, 2010, 2007, 2003, 2002, 2000, 98 and 97 and 8, 7, Vista, XP, Windows 2000 ( 32bit/ 64bit )

Get More info:      OST to PST    ||    EDB to PST    ||    NSF to PST



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After delete the email document from ICN, the “uploaded successfully” tab was still in Outlook.

The end User select the email message on outlook and add/upload to ICN repository with entry template. Added document can be found in the repository. Email message on outlook have a tag for “Uploaded successfully”.

User delete the email message in the repository. But when user checks back the MS Outlook message. The indicative tag is still showing on the message.

As shown below, those emails uploaded to DMS will have the orange toggle indicator whereas when the email was deleted in DMS, the indicator is not removed.

![alt text][1]

CPE and CEC version; ICN version 3.0.1; Navigator for office plugin 3.0.1

Could you please confirm if this is working as designed? Is the tag just described that the emails have ever been uploaded to ICN successfully? Even if after upload, the document was deleted.

[1]: /answers/storage/temp/19286-download.png


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7022436: Outlook becomes unresponsive when uploading large files using the Filr plugin

This document (7022436) is provided subject to the disclaimer at the end of this document.


Micro Focus Filr

Micro Focus Filr plugin for MS Outlook


If you choose to perform any action in Microsoft Outlook when the Filr Outlook Plugin is uploading several large files to Filr server, Outlook might not respond temporarily until the files are uploaded to the Filr server.


A fix for this issue is available in the Filr 3.3 Update. With the updated Filr plugin for Outlook, multi-threading for file uploads will be supported.


This Support Knowledgebase provides a valuable tool for NetIQ/Novell/SUSE customers and parties interested in our products and solutions to acquire information, ideas and learn from one another. Materials are provided for informational, personal or non-commercial use within your organization and are presented “AS IS” WITHOUT WARRANTY OF ANY KIND.


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Re: Export MBOX from Apple Mac Mail to Outlook PST for Windows

I would like to suggest you MBOX to PST Converter that supports all MBOX files, which is created by more than 20 emails clients including AppleMail, Entourage, Eudora, Postbox, Netscape, PocoMail, Thunderbird, Spicebird, Opera, PowerMail, Claws Mail, Evolution, SeaMonkey, Sylpheed, Mulberry, GyazMail, Gnu, Sparrow, The Bat!, WebMail etc and export emails from them into MS Outlook as well as Windows Live Mail successfully. MBOX Converter software allows to migrate all data or emails from corrupted MBOX files of email clients into PST and EML file format.

Read More: How to Export Apple Mac Mail to Outlook PST for Windows

Thanks & Regards

Selina Jodi


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Export MBOX from Apple Mac Mail to Outlook PST for Windows

I would like to suggest you MBOX to PST Converter that supports all MBOX files, which is created by more than 20 emails clients including AppleMail, Entourage, Eudora, Postbox, Netscape, PocoMail, Thunderbird, Spicebird, Opera, PowerMail, Claws Mail, Evolution, SeaMonkey, Sylpheed, Mulberry, GyazMail, Gnu, Sparrow, The Bat!, WebMail etc and export emails from them into MS Outlook as well as Windows Live Mail successfully. MBOX Converter software allows to migrate all data or emails from corrupted MBOX files of email clients into PST and EML file format.

Read More: How to Export Apple Mac Mail to Outlook PST for Windows

Thanks & Regards

Selina Jodi


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Repair corrupt .pst file in Outlook

To repair corrupt .pst file using manually using scanpst.exe offered by Microsoft, it is totally free for users. If scanpst.exe fails in repairing of corrupt .pst file of MS Outlook then try PST Repair application that allows to repair or restore damage .pst in MS Outlook.

Read More: How to Recover Lost or Deleted Emails, Contacts & Calendar in Outlook 2016, 2013, 2010

Thanks & Regards

Selina Jodi


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Troubleshooting and fixing ‘connection to Microsoft exchange is unavailable’ error

Isn’t it always annoying when we get an error? And it’s especially galling when the error is a cryptic one that doesn’t tell us the cause of the problem. Well, “connection to Microsoft exchange is unavailable” is one such cryptic message that doesn’t tell you much about why there is no connection.

If you’re like me, you’ll probably go through the different possibilities in your mind and try to zone in on the most likely cause of the problem.

Let’s save all this trouble for you. When you see this error message, simply try one of the below options and, hopefully, one of these should fix it for you.

Office 365

If you’re an Office 365 user and you get this message, the most likely cause is a conflict in your username and password. It happens typically when you use the same email address and password for your Office 365 account and for your third-party provider’s login.

Create a new alias

A common way to solve this problem is to create a new alias in Office 365 and use this alias to set up your Outlook.

To do this:

  • Log into your exchange admin center.
  • Navigate to recipients -> mailboxes and click on your mailbox.
  • Next, choose email address and click on the “+” sign.
  • Select the SMTP server and add a new alias to your domain.
  • Use the new alias instead of your email address to set up your Outlook.
  • Finally, when you’re prompted for the login credentials, use the original Office 365 email address, and it should work.

Change the login credentials

An easier way than the previous option is to change the username or password in either Office 365 or your third-party provider, so that the login credentials are unique. You can do it by yourself if you’re the admin. Otherwise, you’ll have to send a request to the system admin.

Outlook 2007/2010

Since Office 365 is a cloud-based app, it’s easy to fix this error. However, if you’re using Outlook 2007 or 2010, the process is going to be a little longer. Here are some of the things you can do to fix “the connection to Microsoft exchange is unavailable” error.

Enable RPC encryption

You’ll get this error message when your RPC encryption is not enabled. By default, the RPC encryption is disabled in Exchange Server 2010 service pack 1, so you’ll have to manually enable it.

Also, you’ll get this message if you’ve disabled the “encrypt data between Microsoft office outlook and Microsoft exchange” option in your profile settings.

To enable RPC encryption in Outlook 2007, follow these steps:

  • Download the latest version of Outlk12.adm group policy template and add it to your domain controller.
  • Open gpedit.msc. The best way to do it is press the Windows key and the “R” key and type out “gpedit.msc” in it.

Run gpedit

  • Next, navigate to User configuration ->administrative templates ->classic administrative templates (adm) ->Microsoft office outlook 2007> Tools.
  • Look for an option called “Enable RPC encryption” and double-click it.
  • In the dialog box, choose “enabled” and click ok.

These steps should enable the RPC encryption in your group policy editor for Outlook 2007.

If you’re using Outlook 2010, navigate to User configuration -> administrative templates (ADM) -> Microsoft outlook 2010-> account settings -> exchange and enable the “Enable RPC encryption” option.

Export registry keys

The “connection to Microsoft exchange is unavailable” error could be because of a problem between your Outlook 2007 and the Microsoft exchange server. You can troubleshoot this error simply by exporting registry keys from a different PC. To do that:

  • Switch to a different PC and open the registry editor on that PC.
  • Navigate to HKEY_CURRENT_USERsoftwareMicrosoftWindows NTCurrent VersionWindows messaging subsystem.
  • Right-click on Windows messaging subsystem and select the “export” option. Give a name for the export file and save it.
  • Transfer this file to your problematic PC and merge it to your registry.

This should fix any errors related to your registry keys.

Update your registry

“The connection to Microsoft Exchange is unavailable” error can also occur due to problems in the registry. Your registry has some important information that Outlook needs to connect to the Microsoft exchange server. If this information is missing, you get the error message.

To fix this error, get the necessary information from a different PC and paste it in the PC that’s throwing this error.

  • Open a PC in which Outlook is working. Press the Windows key + the letter R and type “regedit” in the textbox. This should open your registry editor.

Open regedit

  • Navigate to HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionExplorerUserShell.

Export the registry keys in 'User Shell folder'

  • Right-click on the User Shell folder and choose “export” from the menu.
  • Give a name for this file, and ensure that it has a “.reg” extension.
  • Finally, move this file to the PC where Outlook is not working. Just run this file with “.reg” extension and the details will be automatically added to your registry.

Restart Outlook and try connecting again. This should fix the problem.

Reset your cache

Sometimes, the problem could be with your cache. If it contains outdated data, this can cause “the connection to Microsoft Exchange is unavailable” error. A good way to fix this problem is to use the flushdns command.

This command flushes and resets your DNS cache server, so any old information is deleted. To use this command,

  • Make sure you’re logged in as the admin.
  • Open the command prompt and enter this command:
  • Once this command executes, close the command prompt and try connecting to the Microsoft exchange server.

This should resolve the error if it’s caused by an outdated cache.

Restart your exchange server

Many times, a simple solution is the answer to a complex error like “the connection to Microsoft Exchange is unavailable.” Try restarting your Exchange server and see if the problem is fixed.

To restart your server:

  • Press Windows key + letter R and type “services.msc.” This will open your services window.
  • Look for “Microsoft Exchange,” right click on it, and select the restart option.
  • If you have more than one Microsoft Exchange, make sure to reset all of them.

Try connecting after the Microsoft server restarts.

Look at your antivirus

Though antivirus offers good protection for your system, at times it can also interfere with the way Outlook works. Malwarebytes is one such antivirus that is known to restrict Outlook and its connections. If nothing else works, disable your antivirus and see if you’re able to establish a connection between Outlook and the Microsoft Exchange server. Even consider removing your antivirus temporarily to check if that fixes your error.

In short, “the connection to Microsoft Exchange is unavailable” is a fairly common error and could happen because of a ton of reasons. Since this error is not so self-explanatory, you may have to try different solutions.

If you know any other fix for this error, please share it with us in the comments section.

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