Slow attachments

I’ve seen a number of other people bring this up here. We are experiencing extremely slow attachment downloading. here is an example of how a 2.5mb file takes around 3 minutes to download.:

This is an enterprise server with 256GB Ram and two CPUs with 24 cores each. Internet speed is 248mb download. Every aspect of this server flies, except em Client attachments. we have uninstalled and re-installed em Client, and we have set the options to “Download messages for offline use”

Has anyone found a fix for this? In this environment, users are opening 5-10 attachments per hour, and when it’s taking 3-5 minutes each, they are literally wasting hours every day waiting for attachments to open.

Has anyone found a fix for this yet?


Sorry, no fix but just adding I also have this issue to hopefully raise the priority of the response.

I just have a laptop computer, no server, multiple users, etc. and it just took several minutes to save a relatively small (5MB) attachment.

1 Like

Has anyone found a fix for this? In this environment, users are opening 5-10 attachments per hour, and when it’s taking 3-5 minutes each, they are literally wasting hours every day waiting for attachments to open

Downloading brand new uncached files via a mail client is never going to be as fast as eg: downloading files directly via a browser if that’s what your comparing it too. It’s completely different and yes will allways be much slower even with a fast connection. This happens to myself with any mail client I use when using IMAP or Exchange type accounts.

Also certain types of file attachments can sometimes take longer than others.

Other things that can sometimes make downloading file attachments slower than normal is if you use an eg: Antivirus email scanning program “scanning realtime” on incoming mail or running “VPNs” etc.

So if you have no optional programs running like that and you have a recent version of eM Client and already have selected to download messages and attachments offline selected “as you say”, and fast internet connection, then nothing you can do in the client to speed that up. It’s not a fault with the mail client.

Once the file attachments are downloaded though in eM Client, they are cached and will open instantly the next time. It’s only the initial file attachment download that can take time.

1 Like

Thanks for taking the time to reply.

I think this is specifically an emClient issue, not a mail system or SMTP issue.

Hint one - There is no situation where a 1.5 MB file should take three to five minutes to download with a 250mb internet connection, on an enterprise server, with no other users on the system (tested at night with no other users connected). We also ran multiple speed tests simultaneously to confirm connection speed while downloading.

Hint Two - we tested the exact same scenario with Thunderbird, and it took a second to download the exact same attachment on the same system.

Hint three - we tested the exact same scenario with Outlook and it took a few seconds to download the exact same attachment on the same system.

hint four - we then resent a new email and attempted to do the same through emclient, and again it took over three minutes.

This is clearly an emClient issue. Other mail clients work perfectly well side by side with emClient.

We are working with emClient support to try and resolve this issue currently.

1 Like

Same situation here. Downloading attachments takes so much time on different computers (desktop, laptop). Driving me crazy.

Agree that this issue is specific to eMClient and had it again today.
Never had this issue with Thunderbird.

miércoles 31 mayo 2023 :: 1345hrs (UTC +0100)

I agree that there is an issue that needs to be resolved though believe that will be easier said than done as having run similar tests, I do not experience the performance difference with eMC, however, accept that others do; this is why I believe any issue will be difficult to resolve.
In all instances my attachment of 5mb was there almost instantly.
I used Surfshark VPN with antivirus to slow things down.



¡Buena suerte!

¡Los mejores desde Valencia la soleada y mantente a salvo!

[email protected]

Hablo español, luego portugués, inglés, francés y alemán
con conocimiento de varios otros idiomas.

I am also getting this issue. 1.1MB PDF attachment taking 7 minutes to download over a 75MB connection.

Downloading the same file via GMail is instant.

Also, if you stop a download and restart it, you can never open the file as you get a “corrupted” error.

100% an eMClient problem.

Please see my recent comment here. Even if it is not a Yahoo! account, the setting may help.

Other reports of the same issue, dating back quite a long time:-

Why are attachments so damn slow to download compared to Gmail? - Mail - eM Client

Download attachments is very slow - Mail - eM Client

Slow attachment downloads since 9.2 update - eM Client

Downloading attachments is extremely slow - Mail - eM Client

Downloading attachment (pdf) very slow, ends up with corrupt file - Mail - eM Client

1 Like

I have the same experience too with EM client. As well on a win 10 laptop with high speed internet as on my android telephone…

Pinging on this one…as I am another user with painfully slow attachments. I have been getting some mid-sized PDFs lately from a vendor (between 10-20MB in size), and they are awful to sit and wait while they download. If I use Outlook, they download and open immediately. PC, Pro User, on Windows 11 latest version.

Same situation here. Downloading attachments are very slow :cry:

In addtion to gizmo2501’s list, here are some other threads on the same topic:

Slow to download attachments - Mail - eM Client

Very Slow Download of Video Attachments - Mail - eM Client

Yahoo mail downloading attachments: super slow - Mail - eM Client

You have to read through these threads to find solutions

In a July 2023 post in one of these threads, Gary recommended adding a string parameter to the advanced options box.

He said this downloads attachments in a way that is faster but less reliable, and so it should only be used if you were having a problem.

In a September 2023 post, he pointed out the checkboxes for downloading attachments in Accounts > IMAP > Sync Options.

My understanding is that this basically pre-downloads all the attachments you get locally. (It would be great if those messages and their attachments go back to the server when you move them out of the inbox, but IDK.)

So, those are the two fixes on offer now in one post. I tested both of them and they worked.

1 Like

EDITED: the string worked perfect for me.
Initially it didn’t, but upon a check id misspelt it.

Thanks gary

Did you apply the setting I gave above?

I have tried the setting and also have made the changes to the account settings; attachment download speed is still very slow. We are using the default Windows antivirus, have a gigabit connection and no VPN.

We have to go to the gmail web page and download attachments from there. They come very fast.

Any solution on the horizon? This is ridiculous. The software looks very promising, but there’s no way I’m paying two cents for it with this issue on board. An absolute dealbreaker. This topic dates back to a YEAR ago and the problem apparently persists.

Did you apply the setting I gave above?

I changed an account to Gmail and it’s working so far. So I’m not sure about the solution.