Let's look at what's happened over the years.
1. The telephone line went out for several days, making it impossible for clients to call with projects.
Two things have always helped with this. First, have cable as an ISP. Then, this doesn't happen. Second, if it's just MY phone line, which it always has been, I go next door to Mom's and use her computer to send an e-mail to ALL of my clients about the situation. They can continue to contact me via e-mail, but not telephone. And, I always let them know when the situation is over with.
Alternatively, if your Mom isn't next door, you might be able to get to a library, neighbor, relative, friend, cafe, or some other location to send an e-mail to your clients.
2. My ISP server went down for several days, making it impossible for clients to e-mail me for communication about existing projects, or future projects. Also, I couldn't communicate with them.
So far, I've been lucky enough to NOT have my telephone line go down at the same time as my cable provider!
I just called someone out a few days ago, because this was happening again, every day during primetime work hours, for a month!
I keep a secondary ISP backup account that is dialup. In other words, I have my main ISP connected to my computer and that's cable. I have another computer that I have a different ISP account on, and it's dialup. Two computers, two ISPs, two different modes of connection.
3. The client's server went down for several weeks, making it impossible for clients and myself to e-mail each other, download new project files from them, and more.
This was a combination of solutions.
The client waived some of the deadlines because I couldn't get the files. Other times, I just rearranged my schedule and worked on other books so that I'd be freed up later on when the files became available.
For some projects, the editors had the files at their homes, and e-mailed them to me instead of me retrieving them off the company server. This allowed us to e-mail each other, as well, by using their personal home e-mail addresses. You need to be professional about this, and use them only during the crisis.
Still yet others were able to call me for communication.
4. The client had severe weather damage to their facilities. Editors were on their own at home for several weeks.
