DriveHQ Filemanager unable to connect on iMac. Was previously working. I've been able to log in to the website on the iMac, and can log on to Filemanager on a Windows laptop. Password is correct. Firewall has been disabled also, iMac has been restarted.  It looks like the last synchronisation took place 31 Jan. It is now 12 Feb.

What other options can I try?

I guess it is caused by your FileManager software being too old. We have enhanced the security measures for both the website and the API, which could have affected your version. 

If your iMac is not too old, please upgrade to the latest version DriveHQ FileManager for Mac. You can visit www.DriveHQ.com, click Software, then click "For Mac". If your iMac is too old and you cannot upgrade to the latest version, please send an email to DriveHQ support and tell us your MacOS version. We will try to get you an old version FileManager for Mac that still works.  

 Thanks - but it is the latest version that I was using anyway (V2.2 Build 5211). I did download it again but same issue/error message.

My mac is High Sierra V10.13.6. Everything else works - internet, router etc.

MacOS High Sierra V10.13.6 was released in 2018, about 6-7 years old. It is a little old, but it does support TLS 1.2. Normally it should work fine. But my MacOS version is much higher (Sequoia V15.1). I will ask our engineers to check it. We will update you ASAP.  

In the meantime, if you can upgrade your MacOS, I think it is likely that the problem will be solved. 

We checked the issue very carefully and was unable to duplicate the problem initially. However, we noticed that you've been a member for over 15 years. Now we probably know the cause.

In very old versions of DriveHQ FileManager (for Mac and Windows), SSL(TLS) was an optional security feature. Later on, SSL/TLS became a standard/default feature. So the "Use SSL" checkbox was checked by default. In your case, I guess the checkbox was unchecked and remained unchecked during upgrades.

DriveHQ has enhanced its security features. Now the entire website requires HTTPS with TLS 1.2+. Regular HTTP and SSL 3.0, TLS 1.0, TLS 1.1 are no longer supported. Thus, in FileManager, "Use SSL" must be checked. Otherwise, FileManager won't be able to connect to DriveHQ.com. You can click the Options button in the FileManager toolbar, then click System Options, then check the checkbox. Given the security enhancements, this checkbox is no longer needed. We will remove it in the next version.

Thanks guys - that was it!  I checked the box and after quitting and then re-logging in, it worked and synchronised.