Able to access NAS files, but not email NAS files

Hello. I have a Synology DS212j NAS. I have access from my laptop and Dell XPS 8950 (both with the latest updates for Windows 11). I have mapped folders to both computers for specific folders in the NAS. I am able to access, copy, paste and delete files without any problems. However, on my Dell computer alone, I am unable to email files from the NAS drive. Instead, I have to copy them onto the computer and then email the files. This is true for both web based email and client based email (Thunderbird). The message appears when I click on the NAS folder and I am not able to see the files in the folder before the follow error appears:

Windows does not have access to [NAS IP Address] to share. Please contact your network administrator.

Initially, I thought it was a Synology issue. However, I am able to attach files to emails from my laptop and I have no problems accessing the data, editing the data, deleting or saving the data from either computer. The problem is specifically with emailing. I am now thinking that the problem is the way I have my Dell computer set up, but I don't know what settings will allow me to access the files through email. It is probably the way the attachment is handled that is common to both web based and client based email.

Any ideas? Thanks.

You may have done so already but on your Dell check all the the settings listed in this article for CLIENT computer.

Try adding the IP number of your NAS to trusted sites in Internet Options.