this error appears when im trying to view my created flashboards in remedy user and of course it can't be seen in mid-tier. how will i solve this?

Mmmm Though one...
Are you using the flashboard server or the MidTier to display flashboards?
Try the following
In Admin Tool
File --> Server Information ... --> Advanced --> Default Web Path
Set it to you context path of you midTier eg: http:\\mid-tier\arsys and retry