Yeah, I installed Aspen 7.1 in Win 7 64bit. I followed instruction of someone in this forum. Basicly he said "The problem is that the SQL Manager needs this Backward Compatibility module installed..in x86 form. And the installer of this Backward Compatibility in x86 does not run under x64 OS, hence the error. And the funny thing is, that if you install prior to this the x64 Backward Compatibility, the SQL installer won`t recognize it, it will still give you that error. So, we must trick the system somehow in allowing the x64 Backward Compatibility to be used. For this, search via Google this Backward Compatibility program, find the website and download the x64. After that find in the directories of Aspen DVD kit the 'core' folder and within it the 'SQL2k5Exprs'..now, copy the x64 variant of the Backward Compatibility in that folder, and rename it just like the original one, SQLServer2005_BC.msi, keeping this original one for backup somewhere else." (Sorry, I forgot this guy's name and the link) It works for me in installation part. The problem disturbs me now is while the other parts seems work, the Aspen plus user interface started, saying" connecting to the local server..", waiting for about 20 seconds and quit automatically.