By default the OWA extensions timeout a request to restore an item after 30 seconds.  This was previously not configurable.  In some environments this has posed a problem in the past, where some internal Windows API calls were taking a little bit of time to come back, with, for example, user->group membership details.

A fix for this was introduced and can be used with version EV 8 and  onwards

In Exchange 2003, edit your EVBackend.ini file to include a line like this :

exch1.1.exchange.restorerequesttimeout=45

(where exch1 is the name of the Exchange Server)

You will see a line in the EV OWA Diagnostic log file similiar to this when you've implemented the change :

1/8/2010 5:13:58 AM: [OWAPage::RestoreItem] Item needs restoring

1/8/2010 5:13:58 AM: [OWAPage::RestoreItem] Web app url from session: http://evserver.ev.local/EVAnon

1/8/2010 5:13:58 AM: [OWAPage::RestoreItem] Restore url: http://evserver.ev.local/EVAnon/restoreo2k.asp?vaultid=1E5850B2EA77101459FCD56CBC4D3A5871110000evsite&savesetid=200912080000000~200912080938300000~Z~609C0CD6ACE107F935F3891156085F41&mbx=TCowper@EV.Local&server=exch1&restorelocation=3&foldername=Deleted Items

1/8/2010 5:13:58 AM: [OWAPage::RestoreItem] IWA authentication, using DefaultCredentials

1/8/2010 5:13:58 AM: [OWAPage::RestoreItem] Set timeout: 45000

1/8/2010 5:13:58 AM: [OWAPage::GetUserString] User is already domainuser format

It is not advised to change this to a high value, but some customers have had success in changing this to 45, as an example.