Have had 8 techs out to my house and too many chats and phones calls with Xfinity.
The end result is none of them were of any help and many contradicted each other and said the tests that some of their techs ran could not have been done!
Speedtest.net and Xfinity speed test deliver opposite results.
When you do not clean out your tem files Speedtest.net is highest and Xfinity is the lowest.
When you clean out all the temp files or simply restart your PC then Xfinity will be the highest and Speedtest.net the lowest.
Fast.com tends to track the results of Xfinity speed test.
Also contacted Microsoft about both Windows 7 and Windows 10 and they like Xfiity were of no help.
All the hints and tips from either company do not fix the problem.
Xfinity will test the speed with their special tester and always tell you that you are getting the speed and the problem is your computer.
Microsoft will tell you to try another computer and or OS and blame your computer as well.
One thing for sure ...... if you use a TCP optimzer program and restart your computer or simply restart your computer is works fast agin for a very short period of time.
Neither company wants to invest anytime on their end and they just hope you go away and keep paying each of them your hard earned money.
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