Internet Explorer security warning

We are using FileVistaControl V1.6.
When we download multiple files, we get a Internet Explorer warning.

"To help protect your security, Internet Explorer blocked this site from downloading files to your computer. Click here for options..."

If we accept, we can download the ZIP. But next time we restart Internet Explorer, we get the same warning again.

Our users are complaining about this. What can we do about it?
Adding the site to “Trusted Sites” does not resolve the issue.

Yes, this is an annoying problem caused by IE only. We are trying to find a workaround but in the meantime you can turn it off like this:

To access the setting that controls automatic download blocking
1.    From Internet Explorer, click Tools, and then click Internet Options.
The Internet Options dialog box appears.
2.    Click the Security tab. 
The Internet Options dialog box shows your security levels and zones.
3.    Select the Internet zone, and then click Custom Level.
The Security Settings dialog box appears.
4.    Scroll down to Downloads, and then select the Enable option for Automatic prompting for file downloads.

Adding to “Trusted sites” zone, did not work because this setting is enabled by default in “Medium-Low” and not in “Medium” level. You can either decrease the level of “Trusted sites” to “Medium-Low” level or add the web site to the "Local intranet" zone which at this level by default.

Are there updates regarding a fix or workaround for this issue?

FYI, this problem is now fixed in v1.9:

- Fixed: A confirm dialog box will be displayed when downloading as zip. This will prevent IE from showing the information bar and blocking the download.