Getting error in while loop

I am getting the following error msgs while executing for while loop:

count: command not found
[: -le: unary operator expected

Code lines:
-------------
#!/bin/sh
count =1
while [ $count -le 10 ]
do
echo $count
count = `expr $count + 1`
done

Please help me in creating and executing the above code.

Many thanks in advance.

Duplicate thread ..