Kaspersky changing attached file names like .pdf to .pd_ apparently due to filtering attachments [Merged]

Hello @Bookstore Bill, 

Welcome!

Open Kaspersky Security Cloud application, select Settings → lower left hand corner & bottom of the app window:

Thank you

Flood +

Thanks, that got me past the first hurdle. The next step I have in eliminating the problem of fie extension names having their left letter changed to an underscore is:

“2 In the left part of the window, in the Anti-Virus protection section, select the Mail Anti-Virus subsection.
In the right part of the window, the settings of the Mail Anti-Virus component are displayed”

I did not see the first part but I did seethe second so I clicked on that.

Now I have the mail Anti-Virus settings window open

The next instruction is  “4 In the Mail Anti-Virus window, select the Attachment filter tab.”

I do not see an “Attachment filter tab”

I am trying to follow the institutions in: https://support.kaspersky.com/KESWin/10SP2/en-US/128353.htm

Hello @Bookstore Bill, 

You’re most welcome !
Thank you for posting back

If you’re past the first hurdle, that’s progress

The documentation you’re referring to: Kaspersky Endpoint Security 10 Service Pack 2 for Windows, Filtering email message attachments, from Kaspersky Business product line, is not appropriate for Kaspersky Security Cloud, for Home users. 

• Sadly, Kaspersky haven’t documented the KSC, Mail Anti-Virus - Attachment filter, Configure attachment filter feature

To configure the filter, please follow our images & the guidance from @Katie_A, updated by @Anton Mefodys, in topic Microsoft Outlook 2019 and Attachments, all attachments come with a weird extension_, .xls_ raised by @azucena 

NOTE, configuring the Mail AV, attachment filter only applies to new emails, any emails impacted by Kaspersky’s poor implementation of the feature, remain uncorrected. At this stage, according to Kaspersky, any documents affected by the “bug” must be changed manually.

Thank you

Flood +

Hello everyone,

My MS Outlook 365 MSO 64 bits, changed the attached files names for all attachment types automatically to my new emails sent, and to my historical emails. Actually, it replaced the last letter of the file type with an underscore (“_”); (i.e. “.docx” to “.doc_” or “.pdf” to “.pd_”). I did check my Kaspersky configuration related to this matter, and this is what I had by default:

Settings->Protection->Mail Anti-Virus->Advanced Settings/Protection Scope_incoming and Outgoing messages (checked) / Connectivity_Scan POP3, SMTP,NNTP, and IMAP traffic (checked) _Connect Microsoft Outlook Extension (checked) / Heuristic analysis_Medium scan / Scan of compound files_scan attached files of Microsoft Office formats (checked) / Scan attached archives (checked) / Attachment filter_Rename attachments of selected types

I understand Kaspersky found something up and did the change? If so, how can I resolve the problem? I did not get any message about it. Can I reverse the changes in my historical messages?

Thank you in advance for you help on the matter…

Thank you !

I have two computers, both running Windows 10, Office 365 and KIS.  I received two emails today from different sources, both with images attached.  In both cases, the images had their file extensions modified from JPG to JP_.  When this happens, the files will not open without manual manipulation of the file extension.

I experimented and forwarded new sample images between my two PCs and found that one was inflicted by this issue and one was not.  The only difference I can see between the two systems is the version of KIS (Windows and Office match exactly).

   - PC #1 (issue with modified extensions) -- KIS 21.2.16.590(b)

   - PC#2 (no issues) -- KIS 21.1.15.500 (  c)

Am I barking up the right tree with KIS or am I missing something obvious.  Haven’t experienced this issue before so am kind of stumped.  Thanks!