In one farm we have two solutions deployed one in gac and one in bin. Both are using Microsoft open xml dlls to intract with xls to import/export data. These dlls are in both gac as well as bin of Web application.
One application which is deployed is expected to use dlls from gac and other should use dlls from bin... but movement the we deploy the bin solution, other application which is deployed in the gac not functioning as expected. But strange thing sharepoint not logging anything in log in this regard. Now we are planning to move both application to gac or bin, this solves problem wothout doubt. But am not getting what is the cause this issue. . If any one know plz can you help in this regard... I need to give explanation to this, why this issue?