corrupt pdf's Build 9623 (May 7, 2026)

Problem reported by Jim Heinz - 5/14/2026 at 11:22 AM

Submitted

Is any one having problems with attached pdf's getting corrupt in outlook but are fine in webmail?

I sent the same email to a domain in this setup and also to my outlook email. Outlook email is fine in outlook but the same email to the account on the same server is corrupt in outlook.

Also when sending from webmail to anywhere (including local server) is fine.

Thanks is advance.

Jim Heinz

15 Replies

Reply to Thread

Derek Curtis Replied

5/14/2026 at 4:22 PM

Employee Post

Sorry, Jim, but when you say to your "outlook email" -- is that a Microsoft account? Or is the PDF corrupting in Outlook when using your SmarterMail account, but it's fine in webmail?

Also, how are you connecting to SmarterMail? Just webmail or is it IMAP, MAPI, etc. if using a client. (Like Outlook.)

Derek Curtis

CCO

SmarterTools Inc.

www.smartertools.com

Dave Replied

5/14/2026 at 7:37 PM

Have the same. Outlook using IMAP (I think) doubt it's POP but they might have setup EAS. it's an older version of Outlook (2013 could be 2016) I just blamed it on my customer using an old version of Outlook.

Can check more tomorrow / Monday if you need me to.

Derek Curtis Replied

5/14/2026 at 9:35 PM

Employee Post

Please do, Dave. Thanks.

Derek Curtis

CCO

SmarterTools Inc.

www.smartertools.com

Jim Heinz Replied

5/15/2026 at 3:49 AM

Good Morning Derek,

Sorry, Jim, but when you say to your "outlook email" -- is that a Microsoft account? Or is the PDF corrupting in Outlook when using your SmarterMail account, but it's fine in webmail?

That is correct, I emailed one to my smartermail server and also microsoft's outlook email address

Also, how are you connecting to SmarterMail? Just webmail or is it IMAP, MAPI, etc. if using a client. (Like Outlook.)

We are using MICROSOFT 365 with outlook (active sync)

Microsoft® Outlook® for Microsoft 365 MSO (Version 2604 Build 16.0.19929.20136) 32-bit

. with windows 11 computers.

Our mail server is using Server 2016.

Webmail is fine.

Also, my boss told me he saw this before I upgraded to the lastest version. He saw it on BUILD 9581 also.

Jim Heinz Replied

5/15/2026 at 4:11 AM

Also when sending from webmail the pdf is fine. When I save the pdf to my computer and compose a new email with that attachment, the pdf is fine in google, outlook.com, but get corrupt after it hits my mail server and I open it in outlook. Go to webmail and open the same email It opens no problem.

Jim Heinz Replied

5/15/2026 at 7:48 AM

I installed Thunderbird and used IMAP and I am able to see the pdf.

Also having some problems with excel spreadsheets opening also. Same thing Can view in webmail, thunderbird but not OUTLOOK, says the file is corrupt.

Moblie outlook is fine in all senerio's..

Dave Replied

5/15/2026 at 3:02 PM

Opened ticket [0E6-3199DC6B-00E4] this morning.about this.

Jim Heinz Replied

5/19/2026 at 7:51 AM

Any Updates?

Derek Curtis Replied

5/19/2026 at 8:50 AM

Employee Post

We're still testing, but can't replicate the issue. Jim, we started a ticket with you on this but it looks like we haven't heard back. If you could look for that, and get back to us, that would be great. More scenarios help us test more on our end.

Derek Curtis

CCO

SmarterTools Inc.

www.smartertools.com

Tim Uzzanti Replied

5/19/2026 at 10:36 AM

Employee Post

We have seen this in the past when a firewall would drop packets due to possible intrusion detection signatures, etc. I’m not saying this is the cause in your case, but the fact that we have been unable to replicate the issue is leading us to believe it may be related to something within your network or infrastructure.

Tim Uzzanti

CEO

SmarterTools Inc.

www.smartertools.com