What stage of the installation are you at when the antivirus kicks in? Before or after installation?
It it's during downloading, that's very odd that it would flag an incomplete file and probably a sign that it's throwing false positives.
If it's during or after installation and it's one of the EXEs, it might be because of the way the GRFs are patched or how the client is a slightly changed version of another program (the official client). Once again, it's just throwing false positives.
I'm going to have to go with tsukaza13 on this one and say to disable your antivirus or switch to another one that doesn't throw as many false positives. If you're uneasy about running the installer without a virus check first, you can use online scanners to check it at some point between downloading and running the file. You can find a scanner
here.
It's not the first time an antivirus has flagged RO files as suspicious, but I assure you that any files that are posted by our GM staff will be safe.
