Parece um problema do UAC, visto neste outro problema de configuração (não relacionado a msysgit)
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It can be a issue in the UAC File Virtualization Filter Driver, therefore make sure you’re user account has permission to be able to run applications that need to write to the AppData -> %TEMP%
directory.
SeoUACestiverdesativadoeaexecuçãodainstalaçãocomoAdminnãomudarnada(porquevocêjáéadministrador), você também pode tentar :
- Create a folder name "
Temp
" under C:\
// This step is important, the folder has
to exist.
- Right click the Computer in
Start
menu and select Properties
- Click
Advanced System Setting
- In
System Properties
windows, click Advanced
tab
- Click
Environment Variables
button
- Under
User variables
list, double click TMP
- Change Variable value: from "
%USERPROFILE%\AppData\Local\Temp
" to "C:\Temp
"