Instalation 9.04: Please insert Medium although CD is inside

[haaees]

During the Instalation of 9.04 I get the following message at 75% of the base-system-instalation:

Please insert the medium labeled Ubuntu 9.04 _Jaunty Jackalope_- Release i386 (20090420.1)' in the drive /cdrom/ and to press Enter.

The CD is already in the drive, so I can't proceed with the instalation.

[NilsE]

Assuming you have hit enter and it still hangs you may have a bad CD. Try reburning the CD at a slower burn rate and try again.

[haaees]

I checked the CD, everything is OK.

At another PC the instalation with the same CD was no problem.

I found this bug:

https://bugs.launchpad.net/ubuntu/+s...er/+bug/351053

In the last post, there is a workaround. But this only follows to many other error reports.