Product:
Cognos Controller 10.1.1
Windows 2008 R2 server

Symptom:
Error when you try to import a deployment package to the Content Store from Cognos Connection website in Internet Explorer.

This can happen when you try to import a old deployment file from Cognos 8 to Cognos 10.

Error message:
Illegal InvalidCacheEntry method was called

Possible Solution:
If you click the OK button, it will came up to the results of the import
which was completely successful with no apparent errors produced.

The import choices made were all standard, and “Upgrade all report
specifications” was selected on the last prompt of the import process.

Restart the Internet Explorer browser, and clear the IE cache, will help solve the issue.
The next time you may not have the same issue.

Can also be specific for some web browsers, so try Firefox instead of internet Explorer if that is possible on your client computer.