Windows 10 problem

I have a problem with my PHP forum (operating system Windows 10). I can no longer log in on my PCs, although I can on an IMAC and on an old PC operating Windows Vista and with no Comodo security. I believe Comodo is somehow blocking the log in - perhaps identifying a security risk perhaps. Has anyone come across a similar situation, and is there a way to force Comodo not to block a certain site/URL and if so how?

This may be a problem related to the firewall (typically generates connection error), if web filter a message is displayed.
To solve the firewall problem can add allow tcp / udp and ports used, for example:
allow tcp / udp - ip 1.2.3.4 (your ip if in shared network configure a range of ip address 1.2.3.0 - 1.2.3.25), server ip 5.6.7.8 - Then configure the source ports (this you can leave all and set the destination (s) required port(s). Perhaps the configuration localhost necessary (127.0.0.1 - 127.0.0.1).