There is already a question on this but for some reason the thread is locked (!?) without an answer being given. I am experiencing the following when installing Lenovo's ThinkPad Bluetooth with Enhanced data Rate Software II for Windows 7 (32-bit, 64-bit), Vista (32-bit, 64-bit) - ThinkPad (http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-70042#os): Error 1935: An error occurred during the installation of assembly 'policy.8.0.Microsoft.VC80.CRT,type="win32-policy",version="8.0.50727.42",publicKeyToken="1fc8b3b9a1e18e3b",processorArchitecture="x86".Please refer t... Then rolls back actions and I end up with a system that gives me: BTTray.exe System Error The Program can't start because btwhidcs.DLL is missing from your computer. Try reinstalling the program to fix this problem. Of course re-installing does not help. The fix suggested in the previous version of this question refers to http://support.microsoft.com/kb/970652 . However I do not have Visual Studio (and frankly do not see how that is going to solve my Bluetooth installation issue). For the record I have Microsoft .NET Framework 4 and Windows 7 SP1. A luta continua

Hi Edwin, check this: Error 1935.An error occurred during the installation of assembly 'Microsoft.VC90.ATL,version http://support.microsoft.com/kb/970652 and run the following tool to fix: http://support.microsoft.com/default.aspx?scid=kb;EN-US;946414 André"A programmer is just a tool which converts caffeine into code" Want to install RSAT on Windows 7 Sp1? Check my HowTo: http://www.msfn.org/board/index.php?showtopic=150221

Hi, Edwin My problem is just like yours. And i kinda solved it. i experienced exactly the same error pop-up as i was trying to install lenovo's Thinkpad Bluetooth with Enhanced data Rate Software II for Win7 on my T61p Lapto, and the roll-back, also the notification of missing of btwhidcs.DLL as i start the BTTray.exe thread. gone through the same question post you've mentioned, couldn't figure it out. BUT... HERE's how i solved this UN-INSTALLATION: I run a fully-uninstall TOOL within a Security Software Suite named "Qihu360", which you might haven't heard of, 'cause it is made by a Chinese company, (www.360.cn is its official website) to execute a neat un-installation of that Bluetooth Software. This action , i think , deleted the unuseful legacy files and bad register informations the regular uninstall or roll-back doesn't deal with. RE-INSTALLATION: then i restarted my laptop, just as the app suggested. and restarted the previously not-working setup.exe i downloaded from lenovo's site. and this time, BOOM! it worked well. didn't roll-back, no error pop-up. I'm not so SURE if you can coop with a Chinese software with this chinese UI like me. I used this tool just because i am a Chinese. You might probably got hold of a comparative, similar TOOL maybe Macfee!? Norton? I don't know. I think the problem we both've encountered might be caused by failed installation or incomplete un-installation of the system. the KEY is un-install it first! Hope my words do help you,and things go well. Justin.Z

Doesn't work. Even tried with the "Aggressive" check box checked.