Tcl script error as soon as ModelSim is opened

I have ModelSim ALTERA STARTER EDITION 10.3d.

As soon as I open ModelSim, the jumpstart window appears. When I close it and go to any option on the menu, a dialog box appears which says

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Error in Tcl script

Error: Can't read "_()clients": no such variable

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I have even tried uninstalling and reinstalling but this error persists.

The Stack trace reads as:

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Trace back: can't read "_clients()": no such variable

while executing

"set _currObj $_clients($cid)"

(object "::.bookmarkmgr" method "::vsimwidgets::bookmarkmgr::_setcurrent" body line 11)

invoked from within

"_setcurrent $cid"

(object "::.bookmarkmgr" method "::vsimwidgets::bookmarkmgr::_menu_prepost" body line 16)

invoked from within

"::.bookmarkmgr _menu_prepost .mBar.bookmarks 1 {} 1"

(in namespace inscope "::vsimwidgets::bookmarkmgr" script line 1)

invoked from within

"namespace inscope ::vsimwidgets::bookmarkmgr {::.bookmarkmgr _menu_prepost .mBar.bookmarks 1 {} 1}"

("eval" body line 1)

invoked from within

"eval $post_cmd"

(procedure "::Vsimmenu:DefaultMenuPostCmd" line 41)

invoked from within

"::Vsimmenu:DefaultMenuPostCmd .mBar.bookmarks {namespace inscope ::vsimwidgets::bookmarkmgr {::.bookmarkmgr _menu_prepost .mBar.bookmarks 1 {} 1}} Se..."

(menu preprocess)

<2:C:/altera/15.0/modelsim_ase/win32aloem/tk8.5/bgerror.tcl:92: ::tkerror {can't read "_clients()": no such variable}

<1proc:13: ::tk::dialog::error::bgerror {can't read "_clients()": no such variable}

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How can I resolve this error?