我正在写论文，当我用 texmaker 编译时，出现此错误：
遗憾的是，无法安装 fancyhdr 软件包。请检查日志文件：C:\Users\hicham\AppData\Local\MiKTeX\2.9\miktex\log\pdflatex.log
该日志文件的一些行是
2020-10-29 01:57:43,888+0100 INFO pdflatex - mpm: package repository digest: b097738edfa253d7c454fa07c81fc3c0
2020-10-29 01:57:44,907+0100 FATAL pdflatex - The requested package is unknown.
2020-10-29 01:57:44,908+0100 FATAL pdflatex - Info: ="name="fancyhdr""
2020-10-29 01:57:44,908+0100 FATAL pdflatex - Source: Libraries\MiKTeX\PackageManager\PackageDataStore.cpp
2020-10-29 01:57:44,908+0100 FATAL pdflatex - Line: 394
2020-10-29 01:57:45,066+0100 INFO pdflatex - finishing with exit code 1
2020-10-29 01:57:42,733+0100 INFO pdflatex - enabling input (output) from (to) processes
2020-10-29 01:57:42,835+0100 INFO pdflatex - installing package fancyhdr triggered by tex/latex/fancyhdr\fancyhdr.sty
2020-10-29 01:57:43,596+0100 INFO pdflatex - mpm: starting package maintenance...
2020-10-29 01:57:43,596+0100 INFO pdflatex - mpm: installation directory: "C:\Program Files\MiKTeX 2.9"
2020-10-29 01:57:43,596+0100 INFO pdflatex - mpm: package repository: http://distrib-coffee.ipsl.jussieu.fr/pub/mirrors/ctan/systems/win32/miktex/tm/packages/
maintenance...
2020-10-29 01:57:23,402+0100 INFO pdflatex - mpm: installation directory: "C:\Program Files\MiKTeX 2.9"
2020-10-29 01:57:23,402+0100 INFO pdflatex - mpm: package repository: http://distrib-coffee.ipsl.jussieu.fr/pub/mirrors/ctan/systems/win32/miktex/tm/packages/
2020-10-29 01:57:24,030+0100 INFO pdflatex - mpm: package repository digest: b097738edfa253d7c454fa07c81fc3c0
2020-10-29 01:57:25,600+0100 FATAL pdflatex - The requested package is unknown.
我怎么解决这个问题 ？