Have today downloaded Comodo 5 IS. Why when I try to do a virus scan does it download the update signatures of the original 104MB every time. It is gobbling up my bandwidth big time! When it does download and install it gets to 99% of installation and then tells me its failed and to check internet connectivity which is always on! 
Try manually downloading and installing the initial database as described in this post.
Thanks for your reply. I like the concept of Comodo IS Premium, but why should one have problems with it like the above post? I also did a full scan and the was accepted, but when I reopen CIS it tells me a full scan is necessary again! It does not seem to hold any commands in memory! Have un-installed and gone back to Sygate firewall and Avast a/v!
I canât say why that happened. It is definitely not a normal occurrence.
I have a similar problem and just canât install the update. I disable my antivirus (avg) and then the update starts. But it gets to âfileid.cavâ and stops and tells me that âthe internet connection was gracefully closedâ.
Which is a weird way to tell me that it wonât continue. So - how do I update ???