Hi guys, Can anyone suggest the 'best' configuration for ISA to ISA authentication ? Here is the issue: From my desktop via ISA via Checkpoint on to the internet to a remote ISA publishing OWA, doesn't work I get access denied ? Same for access webfolders, anything that requires authentication. Access is via standard HTTP. Same path as above but remove ISA, it works just fine which suggest the remote ISA/OWA is configured correctly. Desktop via Checkpoint via Remote ISA to OWA/Etc. - Works OK!! These issues only appear when it's ISA to ISA - any suggestions appreciated. Tom.