which plugin is that? Private messages? If yes, try using following custom CSS:

.ow_chat_dialog_wrap .ow_attachments .buttons {
    display: none;}

Yes, pm.

Wrong answers. Thank you.

I have edited my reply. let me know if this won't help

No

The CSS customization above hides the attach button in pop-up message window.
If you need to hide it at Inbox, you should add via Admin Area>Appearance>Edit Them>CSS tab  next CSS code:

.ow_mailbox_form .ow_attachments .buttons{
    display: none;}

TonyKa, if you want to hide an attach button in pop-up message window, please read my post. Or if I misunderstood you, please rephrase your question and give more details.  

Thank you Taissa,

I added it on the EDIT CSS window, pressed apply, nothing changed! its still there! Users can upload on both chat and mail wondows!

How can i remove it ?

Thank you so much!

nothing changed i added both! the UPLOAD is still there...

TonyKa, the CSS changes depends on the theme you are using.
Try this code:

#conversationMessageFormBlock .ow_attachment_icons {display:none !important;}
#dialogsContainer .ow_attachment_icons {display:none !important;}

After changing the code make sure you've cleared browser and site cache. To clear the site cache enable DEV_MODE. Follow the instructions: https://docs.oxwall.org/plugin-tuts:enable-debug .

In case it not work, then please specify what theme you use.

Its not working i am using in one site the Pencil theme (skadate) and on the other site i use the Tenderness.

Its not working in both.   This is for mail or for chat attachements?

I would like to disable both in both sites.

Thank you so much Taissa!!!! you are the best!

Thank you!!!

TonyKa, unfortunately, I cannot help you with SkaDate themes because they are not related to Oxwall. SkaDate has his own technical support so please contact them to solve your issue.

Yes but i need to pay it Taissa,... and in my country now we hardly exist.... Greece... worst than dead.. we pray to die...

TonyKa, I really sympathize with you but I can give you only Oxwall solution. All solutions are listed above are working for Oxwall. I can suggest you to post your question on the Themes forum: http://www.oxwall.org/forum/8 maybe some oxwallers already have a solution.  

Taissa from all these only 

#conversationMessageFormBlock .ow_attachment_icons {display:none !important;}#dialogsContainer .ow_attachment_icons {display:none !important;}

is working and hides buttons on the CHAT ONLY, but dissapears ALSO the Emoticons plugin!!! So users dont see the attache icon but also dont see the add emoticon button... can somebody dissapear only the attachment?

thank you!

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