[Xperia Z General] mervluk:
Is there a problem with the UK Generic stripped ftf. Using flashtool I get the following (using debugging) using a PC running Vista (will try with Windows 7 laptop just in case, though, too):

EDIT confirmed same issue on Windows 7 PC running latest flashtool.

06/026/2014 13:26:54 - DEBUG - (MyLogger.java:100) - <- This level is successfully initialized

06/026/2014 13:26:54 - INFO - (MainSWT.java:829) - Flashtool Version 0.9.13.0 built on 2013-06-04 22:50:00

06/026/2014 13:26:59 - INFO - (MainSWT.java:125) - Device disconnected

06/027/2014 13:27:04 - DEBUG - (Bundle.java:75) - Creating bundle from ftf file : C:\Flashtool\firmwares\C6603_10.4.B.0.569_Stripped.ftf

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : loader.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : kernel.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : elabel-C6603-row_201310171741.1_10.4.B.0.569.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : fotakernel.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : amss_fs_3.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : boot_delivery.xml

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : amss_fs_2.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : amss_fs_1.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : rpm.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : partition-image.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : apps_log.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:75) - Creating bundle from ftf file : C:\Flashtool\firmwares\X10_V1_BLRelock.ftf

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : kernel.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : loader.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : s1boot.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:75) - Creating bundle from ftf file : C:\Flashtool\firmwares\Xperia Z C6603_569_GEN_UK stripped.ftf

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : preset1.ta

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : loader.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : kernel.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : elabel-C6603-row_201310171741.1_10.4.B.0.569.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : fotakernel.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : amss_fs_3.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : boot_delivery.xml

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : amss_fs_2.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : cust-reset.ta

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : amss_fs_1.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : rpm.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : partition-image.sin

06/027/2014 13:27:04 - DEBUG - (Bundle.java:91) - Added this entry to the bundle list : userdata.sin

06/027/2014 13:27:17 - INFO - (MainSWT.java:1061) - Selected Xperia Z C6603 / 569 / GEN_UK stripped

06/027/2014 13:27:17 - INFO - (Bundle.java:405) - Preparing files for flashing

06/027/2014 13:27:17 - DEBUG - (Bundle.java:415) - Created the prepared folder

06/027/2014 13:27:17 - DEBUG - (Bundle.java:324) - Saving entry kernel.sin to disk

06/027/2014 13:27:17 - DEBUG - (BundleEntry.java:41) - Streaming from jar entry : kernel.sin

06/027/2014 13:27:17 - DEBUG - (Bundle.java:328) - Writing Entry to .\firmwares\prepared\kernel.sin

06/027/2014 13:27:17 - DEBUG - (Bundle.java:324) - Saving entry rpm.sin to disk

06/027/2014 13:27:17 - DEBUG - (BundleEntry.java:41) - Streaming from jar entry : rpm.sin

06/027/2014 13:27:17 - DEBUG - (Bundle.java:328) - Writing Entry to .\firmwares\prepared\rpm.sin

06/027/2014 13:27:17 - DEBUG - (Bundle.java:324) - Saving entry elabel-C6603-row_201310171741.1_10.4.B.0.569.sin to disk

06/027/2014 13:27:17 - DEBUG - (BundleEntry.java:41) - Streaming from jar entry : elabel-C6603-row_201310171741.1_10.4.B.0.569.sin

06/027/2014 13:27:17 - DEBUG - (Bundle.java:328) - Writing Entry to .\firmwares\prepared\elabel-C6603-row_201310171741.1_10.4.B.0.569.sin

06/027/2014 13:27:17 - DEBUG - (Bundle.java:324) - Saving entry boot_delivery.xml to disk

06/027/2014 13:27:17 - DEBUG - (BundleEntry.java:41) - Streaming from jar entry : boot_delivery.xml

06/027/2014 13:27:17 - DEBUG - (Bundle.java:328) - Writing Entry to .\firmwares\prepared\boot_delivery.xml

06/027/2014 13:27:17 - ERROR - (Bundle.java:439) -

06/027/2014 13:27:17 - INFO - (FlashJob.java:46) - Cannot open bundle. Flash operation canceled

06/028/2014 13:28:03 - INFO - (TextAreaAppender.java:33) - Log written to C:\Flashtool\flashtool_2014-01-06_01-26-54.log