When I started STATA today, the program said that new update is available. So I let STATA download updates. But I get the following error message. I still have 125GB free memory available in my computer. I don't know where the problem is coming from. Could you help?

. update all
(contacting http://www.stata.com)

downloading documentation files ... I/O error
r(691);


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[P] error . . . . . . . . . . . . . . . . . . . . . . . . Return code 691
I/O error
A filesystem error occurred during input or output. This
typically indicates a hardware or operating system failure,
although it is possible that the disk was merely full and
this state was misinterpreted as an I/O error.

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