He told Colchester's official website: "I was more than happy to sign but because of the weather I couldn't get in. I tried to do it on my fax but my technical knowledge is not very good and I thought it had all gone through."
Walker has been a key figure for the U's since his move and he is still desperate to get a longer deal finalised.
"I'm not sure what's happening to be honest, but as far as I am concerned I am happy to stay for the rest of the season," he added.
"I am just hoping they can sort it out and I can stay until the end of the season because I think we have started something really good here."