[BTS] Error Can't update assemblies.

Removal of the assembly failed. Make sure that all items in the assembly you are trying to remove fulfill the following conditions:
1. Pipelines, maps, and schemas are not being used by Send Ports or Receive Locations in the same or referenced application(s)
2. Roles have no enlisted parties
Database Error:
The DELETE statement conflicted with the REFERENCE constraint "bts_sendport_transform_foreign_transformid". The conflict occurred in database "BizTalkMgmtDb", table "dbo.bts_sendport_transform", column 'uidTransformGUID'.
The DELETE statement conflicted with the REFERENCE constraint "fk_bt_mapspec_bts_item". The conflict occurred in database "BizTalkMgmtDb", table "dbo.bt_MapSpec", column 'itemid'.
The DELETE statement conflicted with the REFERENCE constraint "bts_sendport_transform_foreign_transformid". The conflict occurred in database "BizTalkMgmtDb", table "dbo.bts_sendport_transform", column 'uidTransformGUID'.
The statement has been terminated.
The statement has been terminated.
The statement has been terminated. (mscorlib)

 Reason:

Other orchestration, receive location, send port, send groups were using this dll.

If you can't find where it is, please remove all send, receive point and try again.