I have an .Net app running using an Access database. At times what happens is that the application becomes very slow. When I check the server there is multiple instances of the database open as well as multiple ldb files. I usually stop IIS and delete the ldb files and restart everything and all is well....for a while. I compact the database regularly. Any help would be appreciated.

Is there any way to isolate what the cause is?

Sounds to me like you're not closing recordsets...

Errr... Read through the code and check that every recordset that is opened is also shut?