crystal report getting error

hello, i am created crystal report in 32 bit using visual studio. it works fine localhost. but when i host, getting error. "Could not load file or assembly 'log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304' or one of its dependencies. The system cannot find the file specified. my vps server is 64 bit. how to solve this.