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PAC-12 Error 634

New Poster

PAC-12 Error 634

Trying to access PAC-12 streaming online in home and receive Error 634 when trying to watch Pac-12 and CNN.  We have followed the instructions from numerous posts of uninstalling and reinstalling Silverlight.   We even nuked all registry entries for Silverlight.


In speaking to tech support I was advised to complete a factory reset on my computer.  Really?  It is clear there is a problem with the Silverlight delivery from the Comcast website.  CNN and PAC-12 throw Error 634 while trying to obtain authorization.  There are hundreds who have the same problem.  A simple search on your favorite search engine reveals the various complaints since September.  There is no documentation as to what Error 634 is.  It is frustrating that Comcast Telephone Support advised that I must use this forum to get support for this issue.


I am posting info on my computer to see if a Comcast Tech can provide advice to fix problem.  My computer is 1 year old running W7-64bit with 6 gig of RAM and  a NVIDA GT610 with 2gb of memory.  Comcast is the ONLY site where I can't stream in Silverlight. 


My Device Information My Zip Code: 85719 My Cable Provider: Recommended by Comcast My myDVR Manager Status: Unknown My Set Top Box Names: Unknown My Queue setup: True Facebook Queue Syncing: false Facebook Connect: False My public IP address: My operating system: Windows - Windows NT 6.1 My web browser: Explorer 9 - Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/6.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; MDDC; InfoPath.3; .NET4.0C) My system type: Desktop computer or other device My Move player version: Not Installed My Silverlight version: 5.1.10516.0 My flash version: 11.5 r502 Javascript: enabled Cookies: Enabled (2344 Bytes) Time Information My Clock Time: Sat Dec 1 14:53:16 MST 2012 Server Clock Time: Sat Dec 1 14:53:10 MST 2012

My Account Information Primary Account: False Provider Codes: bq, ce, cd, cf, aw, cg, bv, b, cm, bw, ci, y, bx, bb, bc, bu, by, bs, at, cb, ch, bm, bl, bk, bo, cc, bn Internet Subscriber: False Cable TV Subscriber: True Voice Subscriber: False
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Silver Problem Solver

Re: PAC-12 Error 634

sir I am very sorry to tell you that this is a user to user forum, why comcast would send you here is a joke.  Most who post here know more than the average comcast call rep, but to tell you to reset your pc also is a joke.    I just tried both and they work for me. so something on your system or your area is the issue.  Its very hard to troubleshoot issues like this as everyone has different security, anti virus, firewalls etc.  


Are you signed into your account with the primary users credentials?   All I can tell you is try to disable all antivirus and firewalls and spyware programs and try again.   I would restart first then try that.   your silverlight and flash is up to date.


I see your using ie9, try using google chrome and see if that works, comcast has issues with ie9.  Also try to run the 32 bit versions of ie 9 and chrome, comcast does not play nice in 64bit world.  Thats all I can tell you from one customer to another

New Poster

Re: PAC-12 Error 634



Thanks for the response.  They said go to online chat support and this is the closest I could find.  I have tried from Chrome, Safari, Firefox and IE9 &10 to no avail.  Pop up blockers are off and xfinitytv et al added as trusted websites.  I have killed all malware and firewall software to no avail.  I have a lap top on same network that works fine.  It also has same software and Vipre version.    It is failing on authentication.


I will try 32 bit version of IE. 

Best regards.


Silver Problem Solver

Re: PAC-12 Error 634

they told you to go to chat, not here.  This is the user to user forum.  here is the chat link



New Poster

Re: PAC-12 Error 634

For a year I tried repeatedly uninstalling and reinstalling Silverlight manually.  Finally, after being pointed to the Netflix site for a similar problem, I used Microsoft's automatic "Fixit" tool, and it worked!




Click on the Fixit icon and watch it uninstall/reinstall Silverlight.  Don't know what it does differently than a manual uninstall/reinstall, but it works!  WooHoo!

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