Windows 10: Changes to File Types Blocked in Outlook on the web

Brink · Sep 26, 2019

We will soon be adding several additional file extensions to the BlockedFileTypes property of existing OwaMailboxPolicy objects. This change will prevent Outlook on the web users from downloading attachments that have those file extensions.

Why are we making this change?

We’re always evaluating ways to improve security for our customers, and so we took the time to audit the existing blocked file list and update it to better reflect the file types we see as risks today.

How does this affect me?

The newly blocked file types are rarely used, so most organizations will not be affected by the change. However, if your users are sending and receiving affected attachments, they will report that they are no longer able to download them.

How can I prepare for this change?

If your organization requires that users be able to download attachment of these types from OWA, you should first ensure that our organization's operating systems and application software are up-to-date (in the case files that are opened by application software) or ensure that your users are familiar with the risks associated with the file types (in the case of files that are interpreted by scripting software).

If you want to allow a particular file type to be allowed, you can add that file type to the AllowedFileTypes property of your users' OwaMailboxPolicy objects.

Note: In order to minimize disruption from this change, we will not add a file extension to a policy's BlockedFileTypes list if that extension is already present in the AllowedFileTypes list.

To add a file extension to the AllowedFileTypes list:

$policy = Get-OwaMailboxPolicy [policy name]
$allowedFileTypes = $policy.AllowedFileTypes
$allowedFileTypes.Add(".foo")
Set-OwaMailboxPolicy $policy -AllowedFileTypes $allowedFileTypes

Or if you want (brought to you as part of the service that tries to teach you clever shortcuts) you can use:

Set-OwaMailboxPolicy -Identity "<Policy Name>" -BlockedFileTypes @{Remove=".foo"}

If you wish to remove any extension from BlockedFileTypes list in the future:

$policy = Get-OwaMailboxPolicy [policy name]
$blockedFileTypes = $policy.BlockedFileTypes
$blockedFileTypes.Remove(".foo")
Set-OwaMailboxPolicy $policy -BlockedFileTypes $blockedFileTypes

Again, or:

Set-OwaMailboxPolicy -Identity "<Policy Name>" -BlockedFileTypes @{Remove=".foo"}

In order to determine which OwaMailboxPolicy object governs a particular user's Outlook on the Web experience, run the following commands:

$casMailbox = Get-CasMailbox [email address]
$casMailbox.OwaMailboxPolicy

What file extensions will be added to the BlockedFileTypes list with this change?

The following extensions are used by the Python scripting language:

".py", ".pyc", ".pyo", ".pyw", ".pyz", ".pyzw"

The following extensions are used by the PowerShell scripting language:

".ps1", ".ps1xml", ".ps2", ".ps2xml", ".psc1", ".psc2", ".psd1", ".psdm1", ".psd1", ".psdm1"

The following extensions are used for digital certificates:

".cer", ".crt", ".der"

The following extensions are used by the Java programming language:

".jar", ".jnlp"

The following extensions are used by various applications. While the associated vulnerabilities have been patched (for years, in most cases), they are being blocked for the benefit of organizations that might still have older versions of the application software in use:

".appcontent-ms", ".settingcontent-ms", ".cnt", ".hpj", ".website", ".webpnp", ".mcf", ".printerexport", ".pl", ".theme", ".vbp", ".xbap", ".xll", ".xnk", ".msu", ".diagcab", ".grp"

Security of our customer’s data is our utmost priority, and we hope our customers will understand and appreciate this change. Change can be disruptive, so we hope the information here explains what we’re doing and why.
Click to expand...

Source: https://techcommunity.microsoft.com/...eb/ba-p/874451

:)

CliveChambers1 · Sep 26, 2019

Changing the File Type on an Outlook *.OST file.

I did a stupid thing and inadvertently changed the file type of an Outlook 2016 OST file to a PDF file. I have tried to change the type of file that *.OST is used by to Outlook but Windows 10 does not let me. Does anyone have any suggestions.

Thanks

newtekie1 · Sep 26, 2019

Outlook PST File Problem

Thanks again everyone. I just did an export on the troubled PST file to create a new PST file from it and the file size went from 3.9GB down to 850MB. Then I installed the new PST file into Outlook that I just created and removed the old PST file from Outlook and all seems to be working fine so far. I think I am good now, but I will give it some time just to make sure there are no problems before I delete the old file. Thanks again.
Click to expand...

That is exactly what I was going to suggest. Export everything to another PST file, delete the old(or rather move it out of the default folder) and replace it with the new PST file that you exported.

Munki · Sep 26, 2019

GUIDE:How to transfer contacts from Microsoft Outlook to Gmail

I'm sitting here in the office, its the end of the year in the school system, and several employees transferring to alternative counties. With this it brings loads of transferring contacts to take with them from their company phone. Well, this one in particular sparked a guide idea. So here it is, How to transfer Outlook contacts to your Gmail account.

Step 1: Sign in to your outlook account.
step 2 In the top left hand corner click File > Import/Export > Export to file > Browse to desired place to save your file > export. Be sure you export the file as .csv (comma separated values)
Step 3 Log into your Gmail account
Step 4 Select 'Contacts' In the subsection you will see a 'Import' button on the right-hand side. Click it.
Step 5 Browse to the location where you saved it > Open it > Click Import.

I would have provided pictures, but I use neither Outlook or Gmail. Hope someone somewhere gets some use from this. *Toast :toast:

=Munki=

Windows 10: Changes to File Types Blocked in Outlook on the web

Changes to File Types Blocked in Outlook on the web

Changes to File Types Blocked in Outlook on the web

Changes to File Types Blocked in Outlook on the web

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