Error 0x80070660: The Temp folder is full or inaccessible

When you install software that uses the Microsoft Installer (.msi), the error code 0x80070660 may occur. The following is the entire error message:

0x80070660 - The Temp folder is on a drive that is full or is inaccessible. Free up space on the drive or verify that you have write permission on the Temp folder.

Error 0x80070660 - he Temp folder is on a drive that is full


The above error can occur due to one of the following reasons:

  • The “C:\Windows\Installer” folder is missing. This folder is the Windows Installer Cache folder, which stores essential files for apps installed using Windows Installer. (or)
  • The %temp% folder permissions are incorrect.


To resolve the error 0x80070660 (“ERROR_INSTALL_TEMP_UNWRITABLE”), follow these steps:

Step 1: Create the missing “Installer” folder.

The Windows Installer Cache folder “c:\windows\installer” is an important folder that should not be deleted. If it’s deleted, problems arise when uninstalling, repairing, or updating a program.

To recreate the missing folder, follow the steps below:

Open an admin Command Prompt window and run the following command:

md C:\Windows\Installer

Re-run the installer package now.

If that doesn’t fix the issue, fix your temp folder permissions as mentioned in Step 2 below.

Step 2: Fix the Temp folder permissions

Open an admin Command Prompt window.

Type the following commands exactly as given below, and press Enter after each command:

icacls %temp% /inheritance:r
icacls %temp% /grant %username%:(OI)(CI)F /T /C
icacls %temp% /grant Administrators:(OI)(CI)F /T /C
icacls %temp% /grant System:(OI)(CI)F /T /C
md %temp%\Low
icacls %temp%\Low /setintegritylevel (OI)(CI)low

(For more information on fixing the %temp% folder permissions, check out this article.)

That should resolve the error 0x80070660 when running a .msi setup package.

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Ramesh Srinivasan is passionate about Microsoft technologies and he has been a consecutive ten-time recipient of the Microsoft Most Valuable Professional award in the Windows Shell/Desktop Experience category, from 2003 to 2012. He loves to troubleshoot and write about Windows. Ramesh founded in 2005.

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