This depends on the enzyme, no hard and fast rules exist. Many proteins are killed by the process of drying, others are not. If it can be dried, sensitivity to storage conditions varies, acetone powders for example are usually stored at -80 °C over a dessicant. However, your protein may survive higher temperatures. You could try Brenda (http://www.brenda-enzymes.info) to see if literature info for your enzyme is available, otherwise, you have to create a stability profile (store at different conditions for different time and measure activity) yourself. Note that stability depends strongly on conditions (method of drying, pH, presence of substrate and cofactors, osmolytes...)

Yes in support to Mr. Buxbaum, it depends on type of Enzyme. But, dry condition of en enzyme loss its activity at room temperature. i am facing same problem because i am doing my work on bacterial enzyme to isolate and do enzymatic assay. whatever ifs the condition of the enzyme which you are working on try to keep always at least 4'C.