I used Helios Service Release 2 for android.
I think if you follow the following steps you wont face any error.

step#1 Right click on project package from left side.

step#2 Click Export then select export android application and click next.

step#3 keep the project name default selection.

step#4 Select “Create new keystore” radio button and click browse for location.

step#5 Browse any location you want and type the file name without extension, here I choose C:\Users\quayum\Desktop\selim\selm

step#6 After selecting location, enter password(any password)..then click on Next.

step#7 In Key Creation step Enter data (you can use information as i used or by yourself)and click on Next

step#8 Select Destination location and APK file name(you can use the default apk file name or change it with .apk extension),

Step#9 after that click Finish, that will take a while and close the window.

—-Here your apk file is created as desired location—–

Note: for avoiding file repeating error you can use different location to save the “make” and “apk” file. FYI in step#5 “make” file is created and in step#8 the “apk” file is created.