Update error with installed modules

Hello
When I install modules (themebuilder and/or imagemenu), I permanently receive error messages in the history: drupal can't check for updates, and each page takes more than 1 minute to load.
To resolve this problem I have to uninstall both modules or make the module for updates inactive.
I guess that the problem will persist with other additional modules.
What is the problem ?
Thank you for your answers