Please sign in again. iTunes Match has encountered an error.

That worked!!!!

"Sadly no solution posted here has solved the problem for me. I've deauthorized, reauthorized, logged again, etc, etc, and nothing."

Yep, same here. 😟

iTunes is the worst software I've had the misfortune of using.

Also having same problem on Windows 2000. Add new music to Itunes. Update Itunes match, and same error, I have to readd computer, like it was never done before. And word on the fix yet?

This was posted earlier in the thread by somebody else. I do not know that it will work for your operating system, but it worked for windows 7

Okay, I got mine working, I think...no more lightning bolt through my iTunes Match icon on the Music folder (under library), and now I can update my Match library without issue. Now, I'm not sure exactly what step made it work but, most of all, for Windows 7 users, run iTunes with elevated privileges (which I think is the real trick):

1. Launch iTunes as an admin (right click on your iTunes icon and click "Run as administrator."
2. When iTunes loads, sign out, then sign back in.a) At this point, upon signing back in, my Match icon was gone from the Music folder, and it was looking for me to turn on Match again.
3. De-authorize the computer, then authorize again.
4. Now turn Match back on (the process seems like a quick check, and did not take as long as the first Match scan).
5. After iTunes Match is complete again, I was able to close iTunes open again with "Run as administrator," and my match was all good.
6. Close iTunes and reopen without "Run as administrator" and it's still good, updates Match with no issues.

Now, you might be able to skip 5 and just run without elevated privileges, but I figured just in case iTunes needed to write to a protected folder one last time upon launch. Hope this helps any Windows users out there, not sure if the Mac OS users having issues have something similar to elevated permissions when running an app, but I would try that.

After many annoying sign-in-out-iTunes-match-activation problems I found an easy solution for me. When the iTunes Cloud symbol is broken (and I should sign in again) I just deactivate my notebooks (Windows 7) Wifi (with Fn+F5 for my Thinkpad).Then I call up the Itunes store and iTunes tells my that there is no connection to the internet (most probaply this step is not necessesary). After manual re-activation of my Wifi iTunes seems to re-establish the connection and the Cloud symbol signalizes that iTunes match does work, again.

Hope, this helps.

Nope, this wi-fi juggle didn't work either.

1. Launch iTunes as an admin (right click on your iTunes icon and click "Run as administrator."
2. When iTunes loads, sign out, then sign back in.a) At this point, upon signing back in, my Match icon was gone from the Music folder, and it was looking for me to turn on Match again.
3. De-authorize the computer, then authorize again.
4. Now turn Match back on (the process seems like a quick check, and did not take as long as the first Match scan).
5. After iTunes Match is complete again, I was able to close iTunes open again with "Run as administrator," and my match was all good.
6. Close iTunes and reopen without "Run as administrator" and it's still good, updates Match with no issues.

This solution worked for me. I didn't bother with step 5.

Another me too, from France...

And the tips givn earlier unfortunalty won't work on my computer, I still have to de-log, re-log everytime... pretty annoying 😟

I too was having this issue. Windows 7 x64 Professional SP1. The solution outlined above fixed the problem. However this is definitely something Apple should be fixing. Requiring iTunes to be run with administrative privileges (even just long enough to fix the problem) shows that they've dropped the ball somewhere when it comes to the Windows port.

Worked for me on brazilian portuguese iTunes! Thanks!

Unfortunately it doesn’t work for me. I've tried many times and get same sh...

Apple should fix this issue and don’t spend our time for our money.

I posted this to another post but figured it may help here also:

Ok this may or may not solve it for people out there but I, after posting the last post, complaints coming from both my wife and mother about pages not working for them. 1 being the university page that my wife was using to submit her homework and the other being a site that my mother was visiting for a upcoming car purchase. I then realized that I recently changed some settings on my router's firewall (wrt610n, under security->firewall settings) web filter there is a check box for

Proxy Java ActiveX Cookies

not sure which was needed to complete the upload/verification or connection to itunes match but once they were all deselected my mom, my wife and my self were all able to connect to the pages we wanted and to use itunes match.

so check firewall settings that black the aforementioned and maybe it may help.

sorry for the wall of text but hope it helps.

me too...

This was happening to me, but I figured it out.

I had several DJ mixes in iTunes that were over 60 minutes long. I deleted any tracks over 30 minutes long from iTunes and never received an error message again.

Basically, delete any songs/mixes the are over 30 minutes long and you should be fine. Is this ideal? Not so much, but until the servers can handle such a large chunk of data, this is your best bet,

Cheers.

I'm seeing that exact behavior, only the long files cause the issue. Something must have changed in the last few months as I had no issue with these files till the beginning of this year.