My browsers won't play videos!

[Jurnee]

Firefox and Chrome will no longer play videos on my PC. On Firefox, this problem is preceded by Firefox freezing and an error message saying that Shockwave Flash my be busy. The only way to get Firefox to unfreeze is to stop the plug-in. For some reason they will both play videos when I boot my pc into safemode. Also, I don't know if this is related but, when I try to open Steam or any of my Steam games, brings up a window and says that it is searching for updates, then it verifies the installation, and never opens Steam or the games. I ran the sfc/scannow command on the advice of a friend and it said that there were corrupt files but it could not fix some of them. Please help.

Edit: I forgot to mention that videos stored on my hard drive also would not work. However, I may have resolved the issue on my own. I believe it may have been a problem with Skype as, since I changed the settings to where Skype does not open on startup, it has not happened (knock on wood).

 

[Tradesman1]

Have you run a virus and a malware scan?, Checked for add-ons in FF

 

[Jurnee]

Have you run a virus and a malware scan?, Checked for add-ons in FF

Yes, this is always the first thing I do.

 

[Tradesman1]

Is Adobe flash player loaded? Might want to reinstall if already installed - might be corrupt. Also can check for corrupt win files and check the HD for errors - to do this go to the command prompt as Administrator and to run the file check run the command

SFC /SCANNOW

to run the diskcheck (and this can take hours, I run it overnight while sleeping) run the command

CHKDSK /F /R

 

[Jurnee]

Is Adobe flash player loaded? Might want to reinstall if already installed - might be corrupt. Also can check for corrupt win files and check the HD for errors - to do this go to the command prompt as Administrator and to run the file check run the command

SFC /SCANNOW

to run the diskcheck (and this can take hours, I run it overnight while sleeping) run the command

CHKDSK /F /R

I have already uninstalled and reinstalled flash a few times and that did nothing. Also, as I mention in the original post, I ran the sfc/scannow command on the advice of a friend and it said that there were corrupt files but it could not fix some of them. Also, I already did a disk check, which fixed it temporarily, but the next time I rebooted the problem happened again.