"Failed to connect to browser, Timeout after 15 seconds"

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Firefox 4.0 or higher

When starting to record or replay (with Firefox 4.0 or higher) you see this error message in Firefox itself:

TypeError: Components.classes[cid] is undefined

When waiting for a while Squish terminates the recording/replaying and has these entries in the Runner/Server Log:

S: Failed to connect to browser

S: Timeout after 15 seconds

Possible Causes

Firefox 4.0 or higher: Choosing wrong Firefox version in Squish setup

This can be caused when choosing any other entry but “Firefox 4.0 to 6.x” in Squish’s setup program (despite having Firefox 4.0 or higher installed).

To correct this please run <SQUISH_DIR>/setup again and choose the entry “Firefox 4.0 to 6.x”. Then try to record or replay again.