Rick, Thanks a lot for your information. I am still running Citrix on W2000 so I have installed the following hotfixes and they helped. I am not sure which one helped as both of them are related to session issue: - PSE400R03W2K008 - PSE400R03W2K014 Although Citrix says nothing that the hotfixes solves Macintosh connection issue as a matter of fact they do. Thanks, Zygmunt Cwalinski, Metroland Media Group ________________________________ From: thin-bounce@xxxxxxxxxxxxx [mailto:thin-bounce@xxxxxxxxxxxxx] On Behalf Of Rick Mack Sent: 15-05-2007 6:38 AM To: thin@xxxxxxxxxxxxx Subject: [THIN] Re: Black screen when connect to Citrix Hi Zygmunt, R03 breaks earlier thin clients using thinwire version 1. However there's a hotfix PSE400R03W2K3020 (replaces PSE400R03W2K3001) that fixes the thinwire issues and may help you. regards, Rick -- Ulrich Mack Commander Australia On 5/15/07, Cwalinski, Zygmunt <zcwalinski@xxxxxxxxxxxxx> wrote: I have applied Rollup 3 to our Citrix Presentation Server 4.0 last week. Generally everything looks good but I have two MAC users who get only black screen when they connect to their Citrix session. I don' t know if it is Rollup issue, maybe it is just coincidence. Do you have any idea what the reason is? We have cleared Mac application cache, recreated the connection but still they can see only black screen. Thanks, Zygmunt Cwalinski, System Analyst Network Services 905-281-5583