Knowledge base KB0230

Conflict with Cylance security tool: think-cell's automatic update fails


I have the security tool Cylance installed and think-cell's automatic update is failing. If I start PowerPoint or Excel after an Office update, think-cell tries to install a compatible version, but the update fails.

think-cell update fails.

Depending on the Cylance settings, another notification may appear, mentioning that executing a .TMP file was blocked by Cylance:

blocked by Cylance.


Affected customers informed us that the problem was fixed in Cylance version 1560 and later.


think-cell's automatic update (see A.1.3 Automatic Updates) makes sure you have the latest build with the latest improvements. If an update is available it will be downloaded and installed automatically in the background.

Depending on the installation context, it is downloaded into C:\Windows\Temp (per-machine installation) or %LOCALAPPDATA%\Temp (per-user installation) and executed from there.

During an automatic update, think-cell will log that an update is available and the download is started:

Request think-cell update from
Update request succeeded and update is available

However, if an older version of Cylance is available the installation fails with APIERR 5 Access is denied.:


Note: The .TMP file with the random file name is think-cell's .exe installer.

Contact support

If you still have this issue with Cylance version 1560 or later, please contact our support team.